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%I #9 Jul 29 2020 16:38:23
%S 1,135,891,1521,3375,5733,10935,11907,41067,43875,84375,89667,92781,
%T 98865,107811,108927,154791,185625,200655,216513,226233,273375,274625,
%U 287469,307125,336141,416745,448335,480249,544635,557375,570375,590625,627669,628849,648675,692055,823875,885735,931095,968877,1071875,1108809,1131165
%N Odd numbers k such that rad(k) divides sigma(k).
%C Only a minority of terms seem to be also in A228058: 5733, 92781, 2069613, 3341637, 4179357, 5929605, 60998353, 67637349, 89162541 among the first 216, the five of them which occur also in A263983.
%C Question: Is the intersection with A336553 empty?
%H Antti Karttunen, <a href="/A336554/b336554.txt">Table of n, a(n) for n = 1..216</a>
%H <a href="/index/O#opnseqs">Index entries for sequences where odd perfect numbers must occur, if they exist at all</a>
%o (PARI) isA336554(n) = if(!(n%2),0,!(sigma(n) % factorback(factorint(n)[, 1])));
%Y Odd terms of A175200.
%Y Cf. A000203, A007947, A228058, A263983.
%Y Cf. also A336553.
%K nonn
%O 1,2
%A _Antti Karttunen_, Jul 28 2020
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