Question

Is there a pattern behind prime numbers? ​

Answer 1

Answer:

A clear rule determines exactly what makes a prime: it's a whole number that can't be exactly divided by anything except 1 and itself. But there's no discernable pattern in the occurrence of the primes. ... That's because after the number 5, there are only four possibilities — 1, 3, 7 and 9 — for prime last digits.