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Hi, could any one explain how to find the amount of prime numbers between numbers?

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DescriptionA prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself.

The first 25 prime numbers (all the prime numbers less than 100) are: 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



I hope it helps :)
User Ptay
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Explanation;

A prime number is a positive integer that has exactly two positive integer factors, 1 and itself.

Note that the definition of a prime number doesn't allow 1 to be a prime number:

1 only has one factor, namely 1.

Prime numbers have exactly two factors, not "at most two" or anything like that. When a number has more than two factors it is called a composite number.

Prime Numbers between 1 and 200 are;

{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}

So the above listed examples are prime numbers because they have only two factors.

User Oleg Shulakov
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