Talk:De Polignac numbers: Difference between revisions

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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.
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 N from each, and check if the remainder is a prime. If any is, it is '''not''' a de Polignac number. Short circuit and move on. --[[User:Thundergnat|Thundergnat]] ([[User talk:Thundergnat|talk]]) 22:04, 27 September 2022 (UTC)
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. --[[User:Thundergnat|Thundergnat]] ([[User talk:Thundergnat|talk]]) 22:04, 27 September 2022 (UTC)

Revision as of 02:20, 28 September 2022

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)