Math 2.0

definition

Prime number

Definition

A prime number is a natural number pp such that p>1p > 1 and the only positive divisors of pp are 11 and pp.

Remarks

The first prime numbers are 2,3,5,7,11,132, 3, 5, 7, 11, 13. The number 22 is the only even prime. The number 11 is not prime by this definition. This choice makes the prime factorization of each integer unique. A natural number n>1n > 1 that is not prime is a composite number. An equivalent property for p>1p > 1 is Euclid's lemma: if p∣abp \mid a b, then p∣ap \mid a or p∣bp \mid b.

Explanations

L1 human

A prime number is a number greater than 11 that you cannot split as a product of two smaller natural numbers. For example, 77 is prime, but 6=2⋅36 = 2 \cdot 3 is not. The primes are the building blocks of the natural numbers under multiplication.

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Sources

  1. Web https://en.wikipedia.org/wiki/Prime_number, Definition and examples