Talk:De Polignac numbers

From Rosetta Code
Revision as of 02:20, 28 September 2022 by Thundergnat (talk | contribs) (→‎Efficient algorithm: reword, correct order of operations)

Efficient algorithm

There is a quite efficient algorithm to find de Polignac numbers that several entry authors seem to have overlooked.

It is not necessary to test add every power of 2 less than N with every prime less than N and check if the sum is N.

Simply find the powers of 2 less than N, subtract each from N, and check if any remainder is a prime. If any is, it is not a de Polignac number. Short circuit and move on. --Thundergnat (talk) 22:04, 27 September 2022 (UTC)