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.
%I A294628 #28 Mar 04 2018 04:46:36 %S A294628 4,12,12,28,12,52,12,60,36,68,12,132,12,84,76,124,12,172,12,180,92, %T A294628 116,12,292,52,132,108,228,12,340,12,252,124,164,108,444,12,180,140, %U A294628 404,12,436,12,324,268,212,12,612,68,348,172,372,12,532,140,516,188,260,12,868,12,276 %N A294628 a(n) = 8*(sigma(n) - n + (1/2)). %H A294628 Muniru A Asiru, <a href="/A294628/b294628.txt">Table of n, a(n) for n = 1..2000</a> %F A294628 a(n) = 4*A294015(n). %F A294628 a(n) = 8*(A001065(n) + (1/2)). %F A294628 a(n) = 8*(A000203(n) - n + (1/2)). %F A294628 a(n) = A239050(n) - 4*A235796(n). %F A294628 a(n) = A017113(n-1) - 8*A235796(n). %p A294628 with(numtheory): seq(sigma(8*n-1)/8, n=1..10^3); # _Muniru A Asiru_, Mar 04 2018 %t A294628 a[n_] := 8 (DivisorSigma[1, n] - n) + 4; Array[a, 62] (* _Robert G. Wilson v_, Dec 12 2017 *) %o A294628 (GAP) List([1..10^5],n->8*(Sigma(n)-n+(1/2))); # _Muniru A Asiru_, Mar 04 2018 %Y A294628 Partial sums give A294629. %Y A294628 Cf. A001065, A017113, A235796, A237593, A239050, A294015, A294016, A294017, A294630. %K A294628 nonn %O A294628 1,1 %A A294628 _Omar E. Pol_, Nov 05 2017