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 A068078 #16 Aug 19 2024 02:04:03 %S A068078 1,10,34,136,169,2402,5329,21004,38184,41164,54722,458010,776112, %T A068078 1060802,5026562,10800112,11108164,14366402,65676408,87026656, %U A068078 102944992,387999360,1488668112,4414086384,10499710072,28645019964 %N A068078 Numbers k such that (sigma(k)+sigma(k+1))/k is an integer. %C A068078 The quotient (sigma(a(n))+sigma(a(n)+1))/a(n) is equal to 3 or 4 for n <= 33 and equal to 5 for a(34) = 1170035543040. - _Giovanni Resta_, Apr 04 2014 %H A068078 Giovanni Resta, <a href="/A068078/b068078.txt">Table of n, a(n) for n = 1..34</a> %t A068078 For[n=1, True, n++, If[Mod[DivisorSigma[1, n]+DivisorSigma[1, n+1], n]==0, Print[n]]] %Y A068078 Cf. A067806, A068077. %K A068078 nonn %O A068078 1,2 %A A068078 _Dean Hickerson_, Feb 16 2002 %E A068078 a(22)-a(26) from _Donovan Johnson_, Jan 31 2009