primegaps - print large prime gaps primegaps primegaps searches for large gaps in the sequence of primes. The gaps between 2, 3, 5, 7, 11, and so on are 1, 2, 2, 4, and so on. When primegaps sees a new largest gap n , from p-n to p , it prints a line p n r where r is the approximate ratio between the log of n and the log of the log of p . primes(1), primegen(3)