74, according to the rule:
Un = (3n4 - 38n3 + 177n2 - 270n + 160)/8, where n = 1, 2, 3, ...
Chat with our AI personalities
The next number in the sequence 5-7-13-31 is 69.
49
If you meant: 31 37 41 43 47 53 then the next prime number is 59
It is 26 followed by 31
63