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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.

A062967 a(n) = 2*(sigma(n)-n-1)+1, where sigma = A000203, sum of divisors of n.

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%I A062967 #13 Dec 15 2017 17:35:17
%S A062967 -1,1,1,5,1,11,1,13,7,15,1,31,1,19,17,29,1,41,1,43,21,27,1,71,11,31,
%T A062967 25,55,1,83,1,61,29,39,25,109,1,43,33,99,1,107,1,79,65,51,1,151,15,85,
%U A062967 41,91,1,131,33,127,45,63,1,215,1,67,81,125,37,155,1,115,53,147,1,245,1,79,97,127,37,179,1,211,79,87,1,279,45,91,65
%N A062967 a(n) = 2*(sigma(n)-n-1)+1, where sigma = A000203, sum of divisors of n.
%H A062967 Antti Karttunen, <a href="/A062967/b062967.txt">Table of n, a(n) for n = 1..16384</a>
%H A062967 <a href="/index/Su#sums_of_divisors">Index entries for sequences related to sums of divisors</a>
%F A062967 a(n) = 2*A001065(n) - 1. - _Antti Karttunen_, Oct 30 2017
%t A062967 Array[2 (DivisorSigma[1, #] - # - 1) + 1 &, 87] (* _Michael De Vlieger_, Oct 30 2017 *)
%o A062967 (PARI) j=[]; for(n=1,200,j=concat(j,2*(sigma(n)-n-1)+1)); j
%Y A062967 Cf. A000203, A001065, A007593.
%K A062967 easy,sign
%O A062967 1,4
%A A062967 _Jason Earls_, Jul 23 2001