# Talk:Find numbers n in base 2 where n is prime and all it's digits are 1

## Task already exists

Numbers in base 2 whose digits are all one are the powers of 2 minus 1. These are called Mersenne primes and there is already a task for finding them up to a limit. See http://rosettacode.org/wiki/Mersenne_primes. --Chunes (talk) 02:04, 9 March 2021 (UTC)