>all primes greater than 3 are of the form 6k+1 or 6k-1 what's the value in usin... | Hacker News

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		leoff on April 26, 2023 \| parent \| context \| favorite \| on: Why do prime numbers make these spirals? (2019) >all primes greater than 3 are of the form 6k+1 or 6k-1 what's the value in using this "formula"? We could also keep extending this rule, and say that all primes greater than 5 are of the form 30k±1, 30k±7, 30k±11, or 30k±13. Or go further by multiplying coefficient of X with the next primes

Vvector on April 26, 2023 [–]

30k±1 = 6x±1 where x = 5k and so on. Why use four formulas when one will suffice?

zamadatix on April 26, 2023 | [–]

For the same reason you'd use 6x±1 instead of 1+2n or, more basically, n - higher check hit rate at the cost of more complex checking rules.

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