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 A066291 #13 Oct 07 2023 21:39:15
%S A066291 1,34,492,5617,11234,22468,67404,190978,709937,763912,1419874,2839748,
%T A066291 5073996,5446841,7914353,8519244,10893682,11548552,15828706,17126233,
%U A066291 21787364,31657412,34252466,43574728,57928121,63314824,65362092,68504932,73084632,94972236
%N A066291 Numbers m such that DivisorSigma(8*k-4, m) mod m = 0 holds presumably for all k; that is, (8*k-4)-power-sums of divisors of m are divisible by m for all k.
%F A066291 DivisorSigma(8*k-4, m)/m is an integer for k = 1, 2, 3, ..., 200, ...
%e A066291 Tested for each m with k < 200.
%e A066291 Tested for each m with k < 500. - _Sean A. Irvine_, Oct 07 2023
%t A066291 Table[Union[Table[ IntegerQ[DivisorSigma[8*k-4, Part[t, m]]/Part[t, m]], {k, 1, 200}]], {m, 1, Length[t]}]; where t denotes the table of sequence.
%Y A066291 Cf. A066135, A066284, A066289-A066292.
%K A066291 nonn
%O A066291 1,2
%A A066291 _Labos Elemer_, Dec 12 2001
%E A066291 More terms from _Sean A. Irvine_, Oct 07 2023