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 A330580 #7 Dec 20 2019 05:31:11 %S A330580 4,9,604,1849,7123,29588,71056,317238,945414,1347895,3567705,4624025, %T A330580 8518502,1523051853,4353560959,7537630621,24916885136,41483524658, %U A330580 513849020166,1021228997529,1137756574012,1185967711155,1581191501535,1705826324526 %N A330580 Composite numbers n that divide the sum of all composite numbers <= n. %F A330580 a(n) = A002808(A330579(n)). %o A330580 (PARI) s=0; k=0; forcomposite (c=4, oo, k++; s+=c; if (s%c==0, print1 (c", "))) %Y A330580 Cf. A002808, A007506 (prime variant), A330579. %K A330580 nonn,more %O A330580 1,1 %A A330580 _Rémy Sigrist_, Dec 18 2019 %E A330580 a(15)-a(24) from _Giovanni Resta_, Dec 20 2019