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Show HN: Super fast continuous prime sieve

cocalc.com

4 points by ghostforceone 3 years ago · 2 comments

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eesmith 3 years ago

It uses SageMath. Replace ".nbits()" with ".bit_length()" for normal Python (documentation says nbits is an alias: https://doc.sagemath.org/html/en/reference/rings_standard/sa... ).

You'll also need to remove the IPython import if not using a notebook.

Curiously, the listed output includes:

   First 5 primes found and last five primes found [2, 3, 11, 13, 17] 
     ... [4194295, 4194299, 4194301, 4194305, 4194307]
5 and 7 are not on that list. And 4194295 = 5 * 7 * 293 * 409 is not prime, and 4194299 = 29 * 61 * 2371 is also not prime. And 4194305 is clearly not prime either.

How is this supposed to be a prime sieve?

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