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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A145532 Number of numbers removed in each step of Eratosthenes's sieve for 5!.

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%I A145532 #14 Jan 03 2022 02:07:59
%S A145532 59,19,7,4
%N A145532 Number of numbers removed in each step of Eratosthenes's sieve for 5!.
%C A145532 The number of steps in Eratosthenes's sieve for n! is A133228(n).
%C A145532 The number of primes less than 5! is 120 - 59 - 19 - 7 - 4 - 1 = 30 = A003604(5).
%e A145532 a(1)=59 because in first step we removed all numbers divisible by 2 (=60) with the exception of the first one, i.e., 2.
%e A145532 a(2)=19 because the number of numbers divisible by 3 and not divisible by 2 is 20 and we remove all with the exception of the first one, i.e., 3.
%Y A145532 Cf. A003604, A133228, A145532-A145540.
%K A145532 fini,nonn,full
%O A145532 1,1
%A A145532 _Artur Jasinski_, Oct 12 2008