Prime numbers -- only devides by 1 or itself
There are 25 prime numbers between 1 and 100 -- Multiplying Two Primes: Is always a non-prime... 2, 3, 5, 7 (under 10) 11, 13, 17, 19 (under 20) 23, 29 (under 30) 31, 37 (under 40) 41, 43, 47 (under 50) 53, 59 (under 60) 61, 67 (under 70) 71, 73, 79 (under 80) 83, 89 (under 90) 97 (under 100) There are exactly 8 pairs of twin primes under 100. Twin primes are pairs of prime numbers that have a difference of exactly two. [ 1 , 2 , 3 ] The 8 Twin Prime Pairs Under 100 (3, 5) (5, 7) (11, 13) (17, 19) (29, 31) (41, 43) (59, 61) (71, 73) Fast Facts About Twin Primes The Number 5 is unique because it belongs to two different twin prime pairs: (3, 5) and (5, 7). The 6n ± 1 Rule : Except for the very first pair (3, 5), the number right in the middle of every twin prime pair is always a multiple of 6 (like 12, 18, 30, 42, 60, and 72) The 8 Cousin Prime Pairs Under 100 (3, 7) (7, 11) (13, 17) (19, 23) (37, 41) (43, 47) (67, 71) (79, 83) The 15 Sexy Prime Pairs U...
