Problem 52567. Easy Sequences 7: Easy as Composite Pi
37.5% Correct | 62.5% Incorrect
Last Solution submitted on Nov 23, 2022
Lincoln Poon on 25 Oct 2022
I mean...doing this above 1e10 won't be easy anyway, no matter prime or composite.
GeeTwo on 26 Oct 2022
Yes, they're really the same problem, as (designating the composite counting function as κ(n)), κ(n) + 𝜋(n) + 1 = n. There are techniques to do the count without creating an array for x>√n, and even for x>∛n.
Rafael S.T. Vieira on 15 Nov 2022
If anyone does find a way to solve this precisely without some hack, please, publish a scientific paper, and do not post your code here. This problem is not made from an easy sequence at all.
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