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 A348031 #14 Sep 29 2021 04:47:40 %S A348031 1,6,28,120,496,672,8128,30240,32760,523776,23569920,33550336, %T A348031 142990848,1379454720,8589869056,66433720320,137438691328, %U A348031 153003540480,403031236608,14942123276641920,275502900594021408,2305843008139952128,71065075104190073088,154345556085770649600,203820700083634254643200,34384125938411324962897920 %N A348031 Multiply-perfect numbers k that have a divisor d such that sigma(d)*d = k. %C A348031 Multiply-perfect numbers (A007691) that are present in A064987. %C A348031 Note how the first three terms of A005820 are included here, while the next three are in A348032. %C A348031 At least the even terms of A000396 are all present. %H A348031 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a> %Y A348031 Intersection of A007691 and A327165. %Y A348031 Cf. A000396, A005820, A064987, A348032 (complement in A007691), A348035 (subsequence). %K A348031 nonn %O A348031 1,2 %A A348031 _Antti Karttunen_, Sep 26 2021