cp's OEIS Frontend

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.

A078118 n+1 does not divide sigma(n!).

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%I A078118 #10 Feb 16 2019 06:54:16
%S A078118 1,6,22,25,28,30,40,42,46,52,58,60,68,70,72,78,87,88,96,98,102,105,
%T A078118 106,112,114,122,126,128,130,133,138,145,148,150,156,162,166,172,178,
%U A078118 182,190,192,196,198,212,213,217,218,222,225,226,228,232,238,240,250,262
%N A078118 n+1 does not divide sigma(n!).
%H A078118 Vaclav Kotesovec, <a href="/A078118/b078118.txt">Table of n, a(n) for n = 1..8822</a>
%H A078118 Vaclav Kotesovec, <a href="/A078118/a078118.jpg">Plot of a(n)/n for n = 1..8000</a>
%F A078118 a(n) seems to be asymptotic to c*n with c=4.8....
%t A078118 Select[Range[300], Not[Divisible[DivisorSigma[1, #!], # + 1]] &] (* _Vaclav Kotesovec_, Feb 16 2019 *)
%Y A078118 Cf. A062569.
%K A078118 nonn
%O A078118 1,2
%A A078118 _Benoit Cloitre_, Dec 05 2002