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Tutoring: prime numbers definition

Numbers that are only dividing by themselves and by number 1 are called prime numbers.

  • 2 is divisible only by 2 and 1, so 2 is a prime number
  • 3 is divisible only by 3 and 1, so 3 is a prime number
  • 5 is divisible only by 5 and 1, so 5 is a prime number
  • 13 is divisible only by 13 and 1, so 13 is a prime number

1 is not considered prime, so the first prime number is 2 (prime numbers list is starting with the number 2)

Examples of prime numbers, up to 100: 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

EUCLID (300 B.C.) proved that the set of prime numbers is infinite, with no largest prime number.