3, 5
5, 7
11, 13
17, 19
29, 31
41, 43
59, 61
71, 73
There are eight twin prime pairs less than 100 [(3, 5), (5, 7), (11, 13), (17, 19), (29, 31), (41, 43), (59, 61), and (71, 73)].
43
6
Just 3 + 3
Only one pair.
There are eight twin prime pairs less than 100 [(3, 5), (5, 7), (11, 13), (17, 19), (29, 31), (41, 43), (59, 61), and (71, 73)].
Eight pairs.
One pair.
420 has four prime factors. Prime factors don't usually travel in pairs.
43
6
50
One pair: it's a prime number.
There are three pairs.
2 and 3 are the 1st pair
41,2
There are two pairs of prime numbers that express 18 as the sum of two prime numbers: 7 + 11 = 18 and 5 + 13 = 18.