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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.

A336352 Number of prime divisors of sigma(n) that are larger than the largest prime factor of n; a(1) = 0.

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%I A336352 #8 Jul 20 2020 02:08:57
%S A336352 0,1,0,1,0,0,0,2,1,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,1,0,1,0,0,0,0,2,0,0,
%T A336352 0,2,0,0,0,0,0,0,0,0,1,0,0,1,1,1,0,0,0,1,0,0,0,0,0,1,0,0,1,1,0,0,0,0,
%U A336352 0,0,0,2,0,0,1,0,0,0,0,1,1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,1,1,2,0,0,0,0,0
%N A336352 Number of prime divisors of sigma(n) that are larger than the largest prime factor of n; a(1) = 0.
%H A336352 Antti Karttunen, <a href="/A336352/b336352.txt">Table of n, a(n) for n = 1..65537</a>
%H A336352 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A336352 For all n >= 1, a(n) <= A058062(n).
%o A336352 (PARI) A336352(n) = if(1==n,0,my(gp=vecmax(factor(n)[, 1])); #select(p -> (p>gp), factor(sigma(n))[, 1]));
%Y A336352 Cf. A000203, A006530, A058062, A336353 (positions of zeros).
%K A336352 nonn
%O A336352 1,8
%A A336352 _Antti Karttunen_, Jul 19 2020