Which number is not prime

The article deals with the concepts of prime and composite numbers. Definitions of such numbers with examples are given. We give a proof that the number of primes is unlimited and make an entry in the table of primes using the method of Eratosthenes. Proofs will be given as to whether a number is prime or composite.

Yandex.RTB R-A-339285-1

Prime and Composite Numbers - Definitions and Examples

Prime and composite numbers are classified as positive integers. They must be greater than one. Divisors are also divided into simple and compound. To understand the concept of composite numbers, it is necessary to first study the concepts of divisors and multiples.

Definition 1

Prime numbers are integers that are greater than one and have two positive divisors, that is, themselves and 1.

Definition 2

Composite numbers are integers that are greater than one and have at least three positive divisors.

One is neither a prime nor a composite number. It has only one positive divisor, so it is different from all other positive numbers. All positive integers are called natural, that is, used in counting.

Definition 3

prime numbers are natural numbers that have only two positive divisors.

Definition 4

Composite number- this natural number that has more than two positive divisors.

Any number greater than 1 is either prime or composite. From the property of divisibility, we have that 1 and the number a will always be divisors for any number a, that is, it will be divisible by itself and by 1. We give the definition of integers.

Definition 5

Natural numbers that are not prime are called composite numbers.

Prime numbers: 2, 3, 11, 17, 131, 523. They are divisible only by themselves and by 1. Composite numbers: 6, 63, 121, 6697. That is, the number 6 can be decomposed into 2 and 3, and 63 into 1, 3, 7, 9, 21, 63, and 121 into 11, 11, that is, its divisors will be 1, 11, 121. The number 6697 will decompose into 37 and 181. Note that the concepts of prime numbers and relatively prime numbers are different concepts.

To make it easier to use prime numbers, you need to use a table:

A table for all existing natural numbers is unrealistic, since there are an infinite number of them. When the numbers reach sizes of 10000 or 1000000000, then you should think about using the sieve of Eratosthenes.

Consider a theorem that explains the last statement.

Theorem 1

The smallest positive divisor of a natural number greater than 1 other than 1 is a prime number.

Proof 1

Assume that a is a natural number greater than 1, b is the smallest non-one divisor of a. We must prove that b is a prime number using the contradiction method.

Let's say b is a composite number. From here we have that there is a divisor for b , which is different from 1 as well as from b . Such a divisor is denoted as b 1 . It is necessary that condition 1< b 1 < b has been completed.

It can be seen from the condition that a is divisible by b, b is divisible by b 1, which means that the concept of divisibility is expressed in this way: a = b q and b = b 1 q 1 , whence a = b 1 (q 1 q) , where q and q 1 are integers. According to the rule of multiplication of integers, we have that the product of integers is an integer with an equality of the form a = b 1 · (q 1 · q) . It can be seen that b 1 is the divisor of a. Inequality 1< b 1 < b not matches, because we get that b is the smallest positive non-1 divisor of a.

Theorem 2

There are infinitely many prime numbers.

Proof 2

Suppose we take a finite number of natural numbers n and denote as p 1 , p 2 , … , p n . Let's consider a variant of finding a prime number different from the indicated ones.

Consider the number p, which is equal to p 1 , p 2 , … , p n + 1 . It does not equal each of the numbers corresponding to primes of the form p 1 , p 2 , … , p n . The number p is prime. Then the theorem is considered to be proved. If it is composite, then we need to take the notation p n + 1 and show divisor mismatch with any of p 1 , p 2 , … , p n .

If this were not so, then, based on the divisibility property of the product p 1 , p 2 , … , p n , we get that it would be divisible by p n + 1 . Note that the expression p n + 1 the number p is divided equals the sum p 1 , p 2 , … , p n + 1 . We get that the expression p n + 1 the second term of this sum, which is equal to 1, must be divided, but this is impossible.

It can be seen that any prime number can be found among any number of given primes. It follows that there are infinitely many prime numbers.

Since there are a lot of prime numbers, the tables are limited to numbers 100, 1000, 10000 and so on.

When compiling a table of prime numbers, one should take into account the fact that such a task requires a sequential check of numbers, starting from 2 to 100. If there is no divisor, it is recorded in the table; if it is composite, then it is not entered in the table.

Let's consider step by step.

If you start with the number 2, then it has only 2 divisors: 2 and 1, which means that it can be entered in the table. Also with the number 3 . The number 4 is composite, it should be decomposed into 2 and 2. The number 5 is prime, which means it can be fixed in the table. Do this up to the number 100.

This method uncomfortable and long. You can make a table, but you have to spend a large number of time. It is necessary to use divisibility criteria, which will speed up the process of finding divisors.

The method using the sieve of Eratosthenes is considered the most convenient. Let's take a look at the tables below. To begin with, the numbers 2, 3, 4, ..., 50 are written.

Now you need to cross out all the numbers that are multiples of 2. Make sequential strikethrough. We get a table of the form:

Let's move on to crossing out numbers that are multiples of 5. We get:

We cross out the numbers that are multiples of 7, 11. Finally the table looks like

Let us pass to the formulation of the theorem.

Theorem 3

The smallest positive and non-1 divisor of the base number a does not exceed a , where a is the arithmetic root of the given number.

Proof 3

It is necessary to designate b smallest divisor composite number a. There is an integer q , where a = b · q , and we have that b ≤ q . An inequality of the form b > q because the condition is violated. Both sides of the inequality b ≤ q should be multiplied by any positive number b not equal to 1 . We get that b b ≤ b q , where b 2 ≤ a and b ≤ a .

It can be seen from the proved theorem that the deletion of numbers in the table leads to the fact that it is necessary to start with a number that is equal to b 2 and satisfies the inequality b 2 ≤ a . That is, if you cross out numbers that are multiples of 2, then the process starts from 4, and those that are multiples of 3 start from 9, and so on up to 100.

Compiling such a table using Eratosthenes' theorem says that when all composite numbers are crossed out, there will remain prime ones that do not exceed n. In the example where n = 50 , we have that n = 50 . From here we get that the sieve of Eratosthenes sifts out all composite numbers that are not greater in value than the value of the root of 50. The search for numbers is done by crossing out.

Before solving, it is necessary to find out whether the number is prime or composite. Divisibility criteria are often used. Let's look at this in the example below.

Example 1

Prove that 898989898989898989 is a composite number.

Solution

The sum of the digits of the given number is 9 8 + 9 9 = 9 17 . So the number 9 17 is divisible by 9, based on the sign of divisibility by 9. It follows that it is composite.

Such signs are not able to prove the primeness of a number. If verification is needed, other steps should be taken. Most suitable way- It's a slew of numbers. During the process, prime and composite numbers can be found. That is, numbers in value should not exceed a . That is, the number a must be decomposed into prime factors. if this is true, then the number a can be considered prime.

Example 2

Determine the composite or prime number 11723.

Solution

Now you need to find all divisors for the number 11723. Need to evaluate 11723 .

From here we see that 11723< 200 , то 200 2 = 40 000 , and 11 723< 40 000 . Получаем, что делители для 11 723 less than number 200 .

For a more accurate estimate of the number 11723, it is necessary to write the expression 108 2 = 11 664, and 109 2 = 11 881 , then 108 2 < 11 723 < 109 2 . It follows from this that 11723< 109 . Видно, что любое число, которое меньше 109 считается делителем для заданного числа.

When decomposing, we get that 2 , 3 , 5 , 7 , 11 , 13 , 17 , 19 , 23 , 29 , 31 , 37 , 41 , 43 , 47 , 53 , 59 , 61 , 67 , 71 , 73 , 79 , 83 , 89 , 97 , 101 , 103 , 107 are all prime numbers. This whole process can be depicted as a division by a column. That is, divide 11723 by 19. The number 19 is one of its factors, since we get division without a remainder. Let's depict the division by a column:

It follows that 11723 is a composite number, because in addition to itself and 1 it has a divisor 19 .

Answer: 11723 is a composite number.

If you notice a mistake in the text, please highlight it and press Ctrl+Enter


In this article, we will study prime and composite numbers. First, we give definitions of prime and composite numbers, and also give examples. After that, we prove that there are infinitely many prime numbers. Next, we write a table of prime numbers, and consider the methods for compiling a table of prime numbers, we will especially carefully dwell on the method called the sieve of Eratosthenes. In conclusion, we highlight the main points that need to be taken into account when proving that a given number is prime or composite.

Page navigation.

Prime and Composite Numbers - Definitions and Examples

The concepts of prime numbers and composite numbers refer to those that are greater than one. Such integers, depending on the number of their positive divisors, are divided into prime and composite numbers. So to understand definitions of prime and composite numbers, you need to have a good idea of ​​\u200b\u200bwhat divisors and multiples are.

Definition.

prime numbers are integers, greater than one, that have only two positive divisors, namely themselves and 1 .

Definition.

Composite numbers are integers greater than one that have at least three positive divisors.

Separately, we note that the number 1 does not apply to either prime or composite numbers. The unit has only one positive divisor, which is the number 1 itself. This distinguishes the number 1 from all other positive integers that have at least two positive divisors.

Given that positive integers are , and that the unit has only one positive divisor, other formulations of the voiced definitions of prime and composite numbers can be given.

Definition.

Prime numbers are natural numbers that have only two positive divisors.

Definition.

Composite numbers are natural numbers that have more than two positive divisors.

Note that every positive integer greater than one is either a prime number or a composite number. In other words, there is not a single integer that is neither prime nor composite. This follows from the divisibility property, which says that the numbers 1 and a are always divisors of any integer a.

Based on the information in the previous paragraph, we can give the following definition of composite numbers.

Definition.

Natural numbers that are not prime are called constituent.

Let's bring examples of prime and composite numbers.

As examples of composite numbers, we give 6 , 63 , 121 and 6697 . This statement also needs an explanation. The number 6, in addition to positive divisors 1 and 6, also has divisors 2 and 3, since 6 \u003d 2 3, therefore 6 is really a composite number. The positive divisors of 63 are the numbers 1 , 3 , 7 , 9 , 21 and 63 . The number 121 is equal to the product of 11 11 , so its positive divisors are 1 , 11 and 121 . And the number 6697 is composite, since its positive divisors, in addition to 1 and 6697, are also the numbers 37 and 181.

In conclusion of this paragraph, I would also like to draw attention to the fact that prime numbers and coprime numbers are far from the same thing.

Prime number table

Prime numbers, for the convenience of their further use, are recorded in a table, which is called the table of prime numbers. Below is prime number table up to 1 000 .

A logical question arises: “Why did we fill out the table of prime numbers only up to 1,000, is it not possible to make a table of all existing prime numbers”?

Let's answer the first part of this question first. For most problems that involve prime numbers, primes up to a thousand will suffice. In other cases, most likely, you will have to resort to some special solution techniques. Although, of course, we can make a table of prime numbers up to an arbitrarily large final integer positive number, be it 10,000 or 1,000,000,000 , in the next paragraph we will talk about methods for compiling tables of prime numbers, in particular, we will analyze the method called .

Now let's look at the possibility (or rather, the impossibility) of compiling a table of all existing prime numbers. We can't make a table of all the primes because there are infinitely many primes. The last statement is a theorem that we will prove after the following auxiliary theorem.

Theorem.

The smallest positive divisor of a natural number greater than 1 other than 1 is a prime number.

Proof.

Let be a is a natural number greater than one, and b is the least positive non-one divisor of a. Let us prove that b is a prime number by contradiction.

Suppose b is a composite number. Then there is a divisor of the number b (let's denote it b 1 ), which is different from both 1 and b . If we also take into account that the absolute value of the divisor does not exceed the absolute value of the dividend (we know this from the properties of divisibility), then the condition 1

Since the number a is divisible by b by condition, and we said that b is divisible by b 1, then the concept of divisibility allows us to talk about the existence of such integers q and q 1 that a=b q and b=b 1 q 1 , whence a= b 1 ·(q 1 ·q) . From it follows that the product of two integers is an integer, then the equality a=b 1 ·(q 1 ·q) indicates that b 1 is a divisor of the number a . Taking into account the above inequalities 1

Now we can prove that there are infinitely many prime numbers.

Theorem.

There are infinitely many prime numbers.

Proof.

Let's assume it's not. That is, suppose that there are only n primes, and these primes are p 1 , p 2 , …, p n . Let us show that we can always find a prime number different from those indicated.

Consider a number p equal to p 1 ·p 2 ·…·p n +1 . It is clear that this number is different from each of the primes p 1 , p 2 , …, p n . If the number p is prime, then the theorem is proved. If this number is composite, then, by virtue of the previous theorem, there is a prime divisor of this number (let's denote it p n+1 ). Let's show that this divisor does not coincide with any of the numbers p 1 , p 2 , …, p n .

If this were not so, then by the properties of divisibility, the product p 1 ·p 2 ·…·p n would be divisible by p n+1 . But the number p is also divisible by p n+1, equal to the sum p 1 ·p 2 ·…·p n +1. This implies that the second term of this sum, which is equal to one, must be divisible by p n+1, and this is impossible.

Thus, it is proved that a new prime number can always be found, which is not contained among any number of prime numbers given in advance. Therefore, there are infinitely many prime numbers.

So, due to the fact that there are infinitely many prime numbers, when compiling tables of prime numbers, they always limit themselves from above to some number, usually 100, 1,000, 10,000, etc.

Sieve of Eratosthenes

Now we will discuss ways of compiling tables of prime numbers. Suppose we need to make a table of prime numbers up to 100 .

The most obvious method for solving this problem is to sequentially check positive integers, starting with 2 and ending with 100 , for the presence of a positive divisor that is greater than 1 and less than the number being checked (from the properties of divisibility, we know that the absolute value of the divisor does not exceed the absolute value of the dividend, different from zero). If such a divisor is not found, then the number being checked is prime, and it is entered in the table of prime numbers. If such a divisor is found, then the number being checked is composite, it is NOT entered into the table of prime numbers. After that, there is a transition to the next number, which is similarly checked for the presence of a divisor.

Let's describe the first few steps.

We start with the number 2. The number 2 has no positive divisors other than 1 and 2 . Therefore, it is prime, therefore, we enter it in the table of prime numbers. Here it should be said that 2 is the smallest prime number. Let's move on to number 3. Its possible positive divisor other than 1 and 3 is 2 . But 3 is not divisible by 2, therefore, 3 is a prime number, and it also needs to be entered in the table of prime numbers. Let's move on to number 4. Its positive divisors other than 1 and 4 can be 2 and 3 , let's check them. The number 4 is divisible by 2, therefore, 4 is a composite number and does not need to be entered in the table of prime numbers. Note that 4 is the smallest composite number. Let's move on to number 5. We check if at least one of the numbers 2 , 3 , 4 is its divisor. Since 5 is not divisible by either 2, or 3, or 4, it is prime, and it must be written in the table of prime numbers. Then there is a transition to the numbers 6, 7, and so on up to 100.

This approach to compiling a table of primes is far from ideal. One way or another, he has the right to exist. Note that with this method of constructing a table of integers, you can use divisibility criteria, which will slightly speed up the process of finding divisors.

There is a more convenient way to compile a table of primes called . The word “sieve” present in the name is not accidental, since the actions of this method help, as it were, to “sift” through the sieve of Eratosthenes integers, large units, in order to separate simple from compound ones.

Let's show the sieve of Eratosthenes in action when compiling a table of prime numbers up to 50.

First, we write down the numbers 2, 3, 4, ..., 50 in order.


The first number written 2 is prime. Now from the number 2 we sequentially move to the right by two numbers and cross out these numbers until we get to the end of the compiled table of numbers. So all numbers that are multiples of two will be crossed out.

The first non-crossed out number after 2 is 3 . This number is prime. Now, from the number 3, we sequentially move to the right by three numbers (taking into account the already crossed out numbers) and cross them out. So all numbers that are multiples of three will be crossed out.

The first non-crossed out number after 3 is 5 . This number is prime. Now, from the number 5, we sequentially move to the right by 5 numbers (we also take into account the numbers crossed out earlier) and cross them out. So all numbers that are multiples of five will be crossed out.

Next, we cross out numbers that are multiples of 7, then multiples of 11, and so on. The process ends when there are no numbers left to cross out. Below is a completed table of primes up to 50 obtained using the sieve of Eratosthenes. All uncrossed numbers are prime, and all crossed out numbers are composite.

Let's formulate and prove a theorem that will speed up the process of compiling a table of prime numbers using the sieve of Eratosthenes.

Theorem.

The least positive non-one divisor of a composite number a does not exceed , where is from a .

Proof.

Let b denote the smallest divisor of the composite number a that differs from unity (the number b is prime, which follows from the theorem proved at the very beginning of the previous paragraph). Then there is an integer q such that a=b q (here q is a positive integer, which follows from the rules of multiplication of integers), and (when b>q, the condition that b is the smallest divisor of a is violated, since q is also a divisor of a due to the equality a=q b ). Multiplying both sides of the inequality by a positive and greater than one integer b (we are allowed to do this), we obtain , whence and .

What does the proved theorem give us regarding the sieve of Eratosthenes?

First, the deletion of composite numbers that are multiples of a prime number b should begin with a number equal to (this follows from the inequality ). For example, crossing out numbers that are multiples of two should start with the number 4, multiples of three - with the number 9, multiples of five - with the number 25, and so on.

Secondly, the compilation of a table of prime numbers up to the number n using the sieve of Eratosthenes can be considered complete when all composite numbers that are multiples of prime numbers not exceeding are crossed out. In our example, n=50 (because we are tabulating primes up to 50 ) and , so the sieve of Eratosthenes must weed out all composite multiples of the primes 2 , 3 , 5 and 7 that do not exceed the arithmetic square root of 50 . That is, we no longer need to search and cross out numbers that are multiples of prime numbers 11 , 13 , 17 , 19 , 23 and so on up to 47 , since they will already be crossed out as multiples of smaller prime numbers 2 , 3 , 5 and 7 .

Is this number prime or composite?

Some tasks require finding out whether a given number is prime or composite. In the general case, this task is far from simple, especially for numbers whose record consists of a significant number of characters. In most cases, you have to look for some specific way to solve it. However, we will try to give direction to the train of thought for simple cases.

Undoubtedly, one can try to use divisibility criteria to prove that a given number is composite. If, for example, some criterion of divisibility shows that the given number is divisible by some positive integer greater than one, then the original number is composite.

Example.

Prove that the number 898 989 898 989 898 989 is composite.

Solution.

The sum of the digits of this number is 9 8+9 9=9 17 . Since the number equal to 9 17 is divisible by 9, then by the criterion of divisibility by 9 it can be argued that the original number is also divisible by 9. Therefore, it is composite.

A significant drawback of this approach is that the criteria for divisibility do not allow us to prove the simplicity of a number. Therefore, when checking a number for whether it is prime or composite, you need to proceed differently.

The most logical approach is to enumerate all possible divisors of a given number. If none of the possible divisors is a true divisor of a given number, then that number is prime; otherwise, it is composite. From the theorems proved in the previous paragraph, it follows that the divisors of a given number a must be sought among prime numbers not exceeding . Thus, the given number a can be successively divided by prime numbers (which are convenient to take from the table of prime numbers), trying to find the divisor of the number a. If a divisor is found, then the number a is composite. If among the prime numbers not exceeding , there is no divisor of the number a, then the number a is prime.

Example.

Number 11 723 simple or compound?

Solution.

Let's find out to what prime number the divisors of the number 11 723 can be. For this, we estimate .

It is quite obvious that , since 200 2 \u003d 40 000, and 11 723<40 000 (при необходимости смотрите статью number comparison). Thus, the possible prime divisors of 11,723 are less than 200. This already greatly simplifies our task. If we did not know this, then we would have to sort through all the prime numbers not up to 200, but up to the number 11 723 .

If desired, you can estimate more accurately. Since 108 2 \u003d 11 664, and 109 2 \u003d 11 881, then 108 2<11 723<109 2 , следовательно, . Thus, any of the primes less than 109 is potentially a prime divisor of the given number 11,723.

Now we will sequentially divide the number 11 723 into prime numbers 2 , 3 , 5 , 7 , 11 , 13 , 17 , 19 , 23 , 29 , 31 , 37 , 41 , 43 , 47 , 53 , 59 , 61 , 67 , 71 , 73 , 79 , 83 , 89 , 97 , 101 , 103 , 107 . If the number 11 723 is divided entirely by one of the written prime numbers, then it will be composite. If it is not divisible by any of the written prime numbers, then the original number is prime.

We will not describe this whole monotonous and monotonous process of division. Let's just say that 11 723

Select a rubric Books Mathematics Physics Control and access control Fire safety Useful Equipment suppliers Measuring instruments (KIP) Humidity measurement - suppliers in the Russian Federation. Pressure measurement. Cost measurement. Flowmeters. Temperature measurement Level measurement. Level gauges. Trenchless technologies Sewer systems. Suppliers of pumps in the Russian Federation. Pump repair. Pipeline accessories. Butterfly valves (disk valves). Check valves. Control armature. Mesh filters, mud collectors, magneto-mechanical filters. Ball Valves. Pipes and elements of pipelines. Seals for threads, flanges, etc. Electric motors, electric drives… Manual Alphabets, denominations, units, codes… Alphabets, incl. Greek and Latin. Symbols. Codes. Alpha, beta, gamma, delta, epsilon… Denominations of electrical networks. Unit conversion Decibel. Dream. Background. Units of what? Units of measurement for pressure and vacuum. Converting pressure and vacuum units. Length units. Translation of length units (linear size, distances). Volume units. Conversion of volume units. Density units. Conversion of density units. Area units. Conversion of area units. Units of measurement of hardness. Conversion of hardness units. Temperature units. Conversion of temperature units in the Kelvin / Celsius / Fahrenheit / Rankine / Delisle / Newton / Reamure scales Units of measurement of angles ("angular dimensions"). Convert units of angular velocity and angular acceleration. Standard measurement errors Gases are different as working media. Nitrogen N2 (refrigerant R728) Ammonia (refrigerant R717). Antifreeze. Hydrogen H^2 (refrigerant R702) Water vapor. Air (Atmosphere) Natural gas - natural gas. Biogas is sewer gas. Liquefied gas. NGL. LNG. Propane-butane. Oxygen O2 (refrigerant R732) Oils and lubricants Methane CH4 (refrigerant R50) Water properties. Carbon monoxide CO. carbon monoxide. Carbon dioxide CO2. (Refrigerant R744). Chlorine Cl2 Hydrogen chloride HCl, aka hydrochloric acid. Refrigerants (refrigerants). Refrigerant (Refrigerant) R11 - Fluorotrichloromethane (CFCI3) Refrigerant (Refrigerant) R12 - Difluorodichloromethane (CF2CCl2) Refrigerant (Refrigerant) R125 - Pentafluoroethane (CF2HCF3). Refrigerant (Refrigerant) R134a - 1,1,1,2-Tetrafluoroethane (CF3CFH2). Refrigerant (Refrigerant) R22 - Difluorochloromethane (CF2ClH) Refrigerant (Refrigerant) R32 - Difluoromethane (CH2F2). Refrigerant (Refrigerant) R407C - R-32 (23%) / R-125 (25%) / R-134a (52%) / Percent by mass. other Materials - thermal properties Abrasives - grit, fineness, grinding equipment. Soil, earth, sand and other rocks. Indicators of loosening, shrinkage and density of soils and rocks. Shrinkage and loosening, loads. Slope angles. Heights of ledges, dumps. Wood. Lumber. Timber. Logs. Firewood… Ceramics. Adhesives and glue joints Ice and snow (water ice) Metals Aluminum and aluminum alloys Copper, bronze and brass Bronze Brass Copper (and classification of copper alloys) Nickel and alloys Compliance with alloy grades Steels and alloys Reference tables of weights of rolled metal products and pipes. +/-5% Pipe weight. metal weight. Mechanical properties of steels. Cast Iron Minerals. Asbestos. Food products and food raw materials. Properties, etc. Link to another section of the project. Rubbers, plastics, elastomers, polymers. Detailed description of Elastomers PU, TPU, X-PU, H-PU, XH-PU, S-PU, XS-PU, T-PU, G-PU (CPU), NBR, H-NBR, FPM, EPDM, MVQ, TFE/P, POM, PA-6, TPFE-1, TPFE-2, TPFE-3, TPFE-4, TPFE-5 (PTFE modified), Strength of materials. Sopromat. Construction Materials. Physical, mechanical and thermal properties. Concrete. Concrete solution. Solution. Construction fittings. Steel and others. Tables of applicability of materials. Chemical resistance. Temperature applicability. Corrosion resistance. Sealing materials - joint sealants. PTFE (fluoroplast-4) and derivative materials. FUM tape. Anaerobic adhesives Non-drying (non-hardening) sealants. Silicone sealants (organosilicon). Graphite, asbestos, paronites and derived materials Paronite. Thermally expanded graphite (TRG, TMG), compositions. Properties. Application. Production. Flax sanitary Seals of rubber elastomers Insulators and heat-insulating materials. (link to the project section) Engineering techniques and concepts Explosion protection. Environmental protection. Corrosion. Climatic modifications (Material Compatibility Tables) Classes of pressure, temperature, tightness Drop (loss) of pressure. — Engineering concept. Fire protection. Fires. Theory of automatic control (regulation). TAU Mathematical Handbook Arithmetic, Geometric progressions and sums of some numerical series. Geometric figures. Properties, formulas: perimeters, areas, volumes, lengths. Triangles, Rectangles, etc. Degrees to radians. flat figures. Properties, sides, angles, signs, perimeters, equalities, similarities, chords, sectors, areas, etc. Areas of irregular figures, volumes of irregular bodies. The average value of the signal. Formulas and methods for calculating the area. Graphs. Construction of graphs. Reading charts. Integral and differential calculus. Tabular derivatives and integrals. Derivative table. Table of integrals. Table of primitives. Find derivative. Find the integral. Diffury. Complex numbers. imaginary unit. Linear algebra. (Vectors, matrices) Mathematics for the little ones. Kindergarten - 7th grade. Mathematical logic. Solution of equations. Quadratic and biquadratic equations. Formulas. Methods. Solution of differential equations Examples of solutions to ordinary differential equations of order higher than the first. Examples of solutions to the simplest = analytically solvable ordinary differential equations of the first order. Coordinate systems. Rectangular Cartesian, polar, cylindrical and spherical. Two-dimensional and three-dimensional. Number systems. Numbers and digits (real, complex, ....). Tables of number systems. Power series of Taylor, Maclaurin (=McLaren) and periodic Fourier series. Decomposition of functions into series. Tables of logarithms and basic formulas Tables of numerical values ​​Tables of Bradys. Probability theory and statistics Trigonometric functions, formulas and graphs. sin, cos, tg, ctg….Values ​​of trigonometric functions. Formulas for reducing trigonometric functions. Trigonometric identities. Numerical methods Equipment - standards, dimensions Household appliances, home equipment. Drainage and drainage systems. Capacities, tanks, reservoirs, tanks. Instrumentation and control Instrumentation and automation. Temperature measurement. Conveyors, belt conveyors. Containers (link) Laboratory equipment. Pumps and pumping stations Pumps for liquids and pulps. Engineering jargon. Dictionary. Screening. Filtration. Separation of particles through grids and sieves. Approximate strength of ropes, cables, cords, ropes made of various plastics. Rubber products. Joints and attachments. Diameters conditional, nominal, Du, DN, NPS and NB. Metric and inch diameters. SDR. Keys and keyways. Communication standards. Signals in automation systems (I&C) Analog input and output signals of instruments, sensors, flow meters and automation devices. connection interfaces. Communication protocols (communications) Telephony. Pipeline accessories. Cranes, valves, gate valves…. Building lengths. Flanges and threads. Standards. Connecting dimensions. threads. Designations, dimensions, use, types ... (reference link) Connections ("hygienic", "aseptic") pipelines in the food, dairy and pharmaceutical industries. Pipes, pipelines. Pipe diameters and other characteristics. Choice of pipeline diameter. Flow rates. Expenses. Strength. Selection tables, Pressure drop. Copper pipes. Pipe diameters and other characteristics. Polyvinyl chloride pipes (PVC). Pipe diameters and other characteristics. Pipes are polyethylene. Pipe diameters and other characteristics. Pipes polyethylene PND. Pipe diameters and other characteristics. Steel pipes (including stainless steel). Pipe diameters and other characteristics. The pipe is steel. The pipe is stainless. Stainless steel pipes. Pipe diameters and other characteristics. The pipe is stainless. Carbon steel pipes. Pipe diameters and other characteristics. The pipe is steel. Fitting. Flanges according to GOST, DIN (EN 1092-1) and ANSI (ASME). Flange connection. Flange connections. Flange connection. Elements of pipelines. Electric lamps Electrical connectors and wires (cables) Electric motors. Electric motors. Electrical switching devices. (Link to section) Standards for the personal life of engineers Geography for engineers. Distances, routes, maps….. Engineers in everyday life. Family, children, recreation, clothing and housing. Children of engineers. Engineers in offices. Engineers and other people. Socialization of engineers. Curiosities. Resting engineers. This shocked us. Engineers and food. Recipes, utility. Tricks for restaurants. International trade for engineers. We learn to think in a huckster way. Transport and travel. Private cars, bicycles…. Physics and chemistry of man. Economics for engineers. Bormotologiya financiers - human language. Technological concepts and drawings Paper writing, drawing, office and envelopes. Standard photo sizes. Ventilation and air conditioning. Water supply and sewerage Hot water supply (DHW). Drinking water supply Waste water. Cold water supply Galvanic industry Refrigeration Steam lines / systems. Condensate lines / systems. Steam lines. Condensate pipelines. Food industry Supply of natural gas Welding metals Symbols and designations of equipment on drawings and diagrams. Symbolic graphic representations in projects of heating, ventilation, air conditioning and heat and cold supply, according to ANSI / ASHRAE Standard 134-2005. Sterilization of equipment and materials Heat supply Electronic industry Power supply Physical reference Alphabets. Accepted designations. Basic physical constants. Humidity is absolute, relative and specific. Air humidity. Psychrometric tables. Ramzin diagrams. Time Viscosity, Reynolds number (Re). Viscosity units. Gases. Properties of gases. Individual gas constants. Pressure and Vacuum Vacuum Length, distance, linear dimension Sound. Ultrasound. Sound absorption coefficients (link to another section) Climate. climate data. natural data. SNiP 23-01-99. Building climatology. (Statistics of climatic data) SNIP 23-01-99. Table 3 - Average monthly and annual air temperature, ° С. Former USSR. SNIP 23-01-99 Table 1. Climatic parameters of the cold period of the year. RF. SNIP 23-01-99 Table 2. Climatic parameters of the warm season. Former USSR. SNIP 23-01-99 Table 2. Climatic parameters of the warm season. RF. SNIP 23-01-99 Table 3. Average monthly and annual air temperature, °С. RF. SNiP 23-01-99. Table 5a* - Average monthly and annual partial pressure of water vapor, hPa = 10^2 Pa. RF. SNiP 23-01-99. Table 1. Climatic parameters of the cold season. Former USSR. Density. Weight. Specific gravity. Bulk density. Surface tension. Solubility. Solubility of gases and solids. Light and color. Reflection, absorption and refraction coefficients Color alphabet:) - Designations (codings) of color (colors). Properties of cryogenic materials and media. Tables. Friction coefficients for various materials. Thermal quantities, including temperatures of boiling, melting, flame, etc…… for more information, see: Adiabatic coefficients (indicators). Convection and full heat exchange. Coefficients of thermal linear expansion, thermal volumetric expansion. Temperatures, boiling, melting, other… Conversion of temperature units. Flammability. softening temperature. Boiling points Melting points Thermal conductivity. Thermal conductivity coefficients. Thermodynamics. Specific heat of vaporization (condensation). Enthalpy of vaporization. Specific heat of combustion (calorific value). The need for oxygen. Electric and magnetic quantities Electric dipole moments. The dielectric constant. Electrical constant. Lengths of electromagnetic waves (a reference book of another section) Magnetic field strengths Concepts and formulas for electricity and magnetism. Electrostatics. Piezoelectric modules. Electrical strength of materials Electrical current Electrical resistance and conductivity. Electronic potentials Chemical reference book "Chemical alphabet (dictionary)" - names, abbreviations, prefixes, designations of substances and compounds. Aqueous solutions and mixtures for metal processing. Aqueous solutions for the application and removal of metal coatings Aqueous solutions for cleaning from carbon deposits (tar deposits, carbon deposits from internal combustion engines ...) Aqueous solutions for passivation. Aqueous solutions for etching - removing oxides from the surface Aqueous solutions for phosphating Aqueous solutions and mixtures for chemical oxidation and coloring of metals. Aqueous solutions and mixtures for chemical polishing Degreasing aqueous solutions and organic solvents pH. pH tables. Burning and explosions. Oxidation and reduction. Classes, categories, designations of danger (toxicity) of chemical substances Periodic system of chemical elements of DI Mendeleev. Mendeleev table. Density of organic solvents (g/cm3) depending on temperature. 0-100 °С. Properties of solutions. Dissociation constants, acidity, basicity. Solubility. Mixes. Thermal constants of substances. Enthalpy. entropy. Gibbs energy… (link to the chemical reference book of the project) Electrical engineering Regulators Uninterrupted power supply systems. Dispatch and control systems Structured cabling systems Data centers

Table of prime numbers from 1 to 10000. Table of prime numbers from 1 to 1000

Below is a table of prime numbers from 2 to 10000 (1229 pieces). Unit not included, sorry. Some feel that the unit is not included because… she can't be there. " A prime number is a number that has two divisors: one and the number itself."And the number 1 has only one divisor, it does not apply to either prime or composite numbers. (An explanatory note from Olga on 09/21/12) However, we remember that prime numbers are sometimes introduced like this: " A prime number is a number that is evenly divisible by one and itself."In this case, one is obviously a prime number.

A table of prime numbers from 2 to 1000. The table of prime numbers from 2 to 1000 is grayed out.

Table of prime numbers from 2 to 1000.
The table of prime numbers from 2 to 1000 is grayed out.
2 3 5 7 11 13 17 19 23 29 31 37
41 43 47 53 59 61 67 71 73 79 83 89
97 101 103 107 109 113 127 131 137 139 149 151
157 163 167 173 179 181 191 193 197 199 211 223
227 229 233 239 241 251 257 263 269 271 277 281
283 293 307 311 313 317 331 337 347 349 353 359
367 373 379 383 389 397 401 409 419 421 431 433
439 443 449 457 461 463 467 479 487 491 499 503
509 521 523 541 547 557 563 569 571 577 587 593
599 601 607 613 617 619 631 641 643 647 653 659
661 673 677 683 691 701 709 719 727 733 739 743
751 757 761 769 773 787 797 809 811 821 823 827
829 839 853 857 859 863 877 881 883 887 907 911
919 929 937 941 947 953 967 971 977 983 991 997
A table of prime numbers from 1000 to 10,000.
1009 1013 1019 1021 1031 1033 1039 1049 1051 1061 1063 1069
1087 1091 1093 1097 1103 1109 1117 1123 1129 1151 1153 1163
1171 1181 1187 1193 1201 1213 1217 1223 1229 1231 1237 1249
1259 1277 1279 1283 1289 1291 1297 1301 1303 1307 1319 1321
1327 1361 1367 1373 1381 1399 1409 1423 1427 1429 1433 1439
1447 1451 1453 1459 1471 1481 1483 1487 1489 1493 1499 1511
1523 1531 1543 1549 1553 1559 1567 1571 1579 1583 1597 1601
1607 1609 1613 1619 1621 1627 1637 1657 1663 1667 1669 1693
1697 1699 1709 1721 1723 1733 1741 1747 1753 1759 1777 1783
1787 1789 1801 1811 1823 1831 1847 1861 1867 1871 1873 1877
1879 1889 1901 1907 1913 1931 1933 1949 1951 1973 1979 1987
1993 1997 1999 2003 2011 2017 2027 2029 2039 2053 2063 2069
2081 2083 2087 2089 2099 2111 2113 2129 2131 2137 2141 2143
2153 2161 2179 2203 2207 2213 2221 2237 2239 2243 2251 2267
2269 2273 2281 2287 2293 2297 2309 2311 2333 2339 2341 2347
2351 2357 2371 2377 2381 2383 2389 2393 2399 2411 2417 2423
2437 2441 2447 2459 2467 2473 2477 2503 2521 2531 2539 2543
2549 2551 2557 2579 2591 2593 2609 2617 2621 2633 2647 2657
2659 2663 2671 2677 2683 2687 2689 2693 2699 2707 2711 2713
2719 2729 2731 2741 2749 2753 2767 2777 2789 2791 2797 2801
2803 2819 2833 2837 2843 2851 2857 2861 2879 2887 2897 2903
2909 2917 2927 2939 2953 2957 2963 2969 2971 2999 3001 3011
3019 3023 3037 3041 3049 3061 3067 3079 3083 3089 3109 3119
3121 3137 3163 3167 3169 3181 3187 3191 3203 3209 3217 3221
3229 3251 3253 3257 3259 3271 3299 3301 3307 3313 3319 3323
3329 3331 3343 3347 3359 3361 3371 3373 3389 3391 3407 3413
3433 3449 3457 3461 3463 3467 3469 3491 3499 3511 3517 3527
3529 3533 3539 3541 3547 3557 3559 3571 3581 3583 3593 3607
3613 3617 3623 3631 3637 3643 3659 3671 3673 3677 3691 3697
3701 3709 3719 3727 3733 3739 3761 3767 3769 3779 3793 3797
3803 3821 3823 3833 3847 3851 3853 3863 3877 3881 3889 3907
3911 3917 3919 3923 3929 3931 3943 3947 3967 3989 4001 4003
4007 4013 4019 4021 4027 4049 4051 4057 4073 4079 4091 4093
4099 4111 4127 4129 4133 4139 4153 4157 4159 4177 4201 4211
4217 4219 4229 4231 4241 4243 4253 4259 4261 4271 4273 4283
4289 4297 4327 4337 4339 4349 4357 4363 4373 4391 4397 4409
4421 4423 4441 4447 4451 4457 4463 4481 4483 4493 4507 4513
4517 4519 4523 4547 4549 4561 4567 4583 4591 4597 4603 4621
4637 4639 4643 4649 4651 4657 4663 4673 4679 4691 4703 4721
4723 4729 4733 4751 4759 4783 4787 4789 4793 4799 4801 4813
4817 4831 4861 4871 4877 4889 4903 4909 4919 4931 4933 4937
4943 4951 4957 4967 4969 4973 4987 4993 4999 5003 5009 5011
5021 5023 5039 5051 5059 5077 5081 5087 5099 5101 5107 5113
5119 5147 5153 5167 5171 5179 5189 5197 5209 5227 5231 5233
5237 5261 5273 5279 5281 5297 5303 5309 5323 5333 5347 5351
5381 5387 5393 5399 5407 5413 5417 5419 5431 5437 5441 5443
5449 5471 5477 5479 5483 5501 5503 5507 5519 5521 5527 5531
5557 5563 5569 5573 5581 5591 5623 5639 5641 5647 5651 5653
5657 5659 5669 5683 5689 5693 5701 5711 5717 5737 5741 5743
5749 5779 5783 5791 5801 5807 5813 5821 5827 5839 5843 5849
5851 5857 5861 5867 5869 5879 5881 5897 5903 5923 5927 5939
5953 5981 5987 6007 6011 6029 6037 6043 6047 6053 6067 6073
6079 6089 6091 6101 6113 6121 6131 6133 6143 6151 6163 6173
6197 6199 6203 6211 6217 6221 6229 6247 6257 6263 6269 6271
6277 6287 6299 6301 6311 6317 6323 6329 6337 6343 6353 6359
6361 6367 6373 6379 6389 6397 6421 6427 6449 6451 6469 6473
6481 6491 6521 6529 6547 6551 6553 6563 6569 6571 6577 6581
6599 6607 6619 6637 6653 6659 6661 6673 6679 6689 6691 6701
6703 6709 6719 6733 6737 6761 6763 6779 6781 6791 6793 6803
6823 6827 6829 6833 6841 6857 6863 6869 6871 6883 6899 6907
6911 6917 6947 6949 6959 6961 6967 6971 6977 6983 6991 6997
7001 7013 7019 7027 7039 7043 7057 7069 7079 7103 7109 7121
7127 7129 7151 7159 7177 7187 7193 7207 7211 7213 7219 7229
7237 7243 7247 7253 7283 7297 7307 7309 7321 7331 7333 7349
7351 7369 7393 7411 7417 7433 7451 7457 7459 7477 7481 7487
7489 7499 7507 7517 7523 7529 7537 7541 7547 7549 7559 7561
7573 7577 7583 7589 7591 7603 7607 7621 7639 7643 7649 7669
7673 7681 7687 7691 7699 7703 7717 7723 7727 7741 7753 7757
7759 7789 7793 7817 7823 7829 7841 7853 7867 7873 7877 7879
7883 7901 7907 7919 7927 7933 7937 7949 7951 7963 7993 8009
8011 8017 8039 8053 8059 8069 8081 8087 8089 8093 8101 8111
8117 8123 8147 8161 8167 8171 8179 8191 8209 8219 8221 8231
8233 8237 8243 8263 8269 8273 8287 8291 8293 8297 8311 8317
8329 8353 8363 8369 8377 8387 8389 8419 8423 8429 8431 8443
8447 8461 8467 8501 8513 8521 8527 8537 8539 8543 8563 8573
8581 8597 8599 8609 8623 8627 8629 8641 8647 8663 8669 8677
8681 8689 8693 8699 8707 8713 8719 8731 8737 8741 8747 8753
8761 8779 8783 8803 8807 8819 8821 8831 8837 8839 8849 8861
8863 8867 8887 8893 8923 8929 8933 8941 8951 8963 8969 8971
8999 9001 9007 9011 9013 9029 9041 9043 9049 9059 9067 9091
9103 9109 9127 9133 9137 9151 9157 9161 9173 9181 9187 9199
9203 9209 9221 9227 9239 9241 9257 9277 9281 9283 9293 9311
9319 9323 9337 9341 9343 9349 9371 9377 9391 9397 9403 9413
9419 9421 9431 9433 9437 9439 9461 9463 9467 9473 9479 9491
9497 9511 9521 9533 9539 9547 9551 9587 9601 9613 9619 9623
9629 9631 9643 9649 9661 9677 9679 9689 9697 9719 9721 9733
9739 9743 9749 9767 9769 9781 9787 9791 9803 9811 9817 9829
9833 9839 9851 9857 9859 9871 9883 9887 9901 9907 9923 9929
9931 9941 9949 9967 9973 end of plate 🙂 !

Article rating:

Loading...
Top