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A comment on All Mersenne prime exponents below 100m tested at least once. Parent comment

Re:All Mersenne prime exponents below 100m tested at least once by linknoid on Friday December 04, 2020 @06:01PM (#25309480)
The simple trick with modulo 7 is take all the 3 bit sequences: (x & 111), (x & 111000) >> 3, (x & 111000000) >> 6, etc. and add them all together. It means you just have to do bitshift + add instead of all the complexity of division. Same applies to higher powers of 2^n-1 as well.
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Re:All Mersenne prime exponents below 100m tested at least once by SamReidHughes on Friday December 04, 2020 @06:23PM (#25309657)
You can also combine those shift/adds by multiplying by a 1001001001 pattern or perhaps some 1000001000001 patterns.
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Re:All Mersenne prime exponents below 100m tested at least once by mlyle on Friday December 04, 2020 @07:54PM (#25310481)
Sure. That's why I said it was the same as the mod 9 tricks in base 10.
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