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 A336464 #27 Aug 06 2020 22:04:26 %S A336464 1,2,28,56,60,84,160,168,528,12936,32760,102960,1097280,1778400, %T A336464 11740302,19183500,25241600,235855620,308308000,317167200,424305000, %U A336464 459818240,704700000,787200000,924924000,1592025435,2701416960,3812244480 %N A336464 Numbers k for which A335915(k), A335915(sigma(k)) and A335915(sigma(sigma(k))) obtain the same value. %C A336464 Numbers k for which A335915(k) = A336455(k) = A336456(k). %C A336464 Numbers k such that both k and sigma(k) are in A336461. %C A336464 Note that a(26) = 1592025435 (originally found by _David A. Corneth_) is an odd term > 1, which factorizes as 3^5 * 7^2 * 11^2 * 5 * 13 * 17, and thus is not of the form of A228058. %C A336464 It appears that if we instead list k such that both k and sigma(k) are in A336458, we will not obtain more than these three terms: 1, 2, 84. %H A336464 <a href="/index/O#opnseqs">Index entries for sequences where odd perfect numbers must occur, if they exist at all</a> %Y A336464 Cf. A000203, A000265, A228058, A335915, A336455, A336456, A336458, A336560. %Y A336464 Intersection of any two of these three sequences: A336461, A336462, A336463. %K A336464 nonn,more %O A336464 1,2 %A A336464 _Antti Karttunen_, Jul 22 2020