%I #12 Jun 18 2019 16:12:16
%S 6,28,496,8128,30240,32760,2178540,23569920,33550336,45532800,
%T 142990848,1379454720,8589869056,43861478400,66433720320,137438691328,
%U 153003540480,403031236608,704575228896,181742883469056,6088728021160320,14942123276641920,20158185857531904,275502900594021408,622286506811515392,2305843008139952128
%N Numbers n for which gcd(2n, sigma(n)) = 2n.
%H Antti Karttunen, <a href="/A325637/b325637.txt">Table of n, a(n) for n = 1..1013</a> (computed from the b-file of A007691 prepared by T. D. Noe, using Flammenkamp's data)
%H <a href="/index/O#opnseqs">Index entries for sequences where any odd perfect numbers must occur</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%o (PARI) isA325637(n) = ((n+n)==gcd(n+n,sigma(n)));
%Y Cf. A000203, A033879, A325636, A325638.
%Y Cf. A000396 (a subsequence).
%Y Subsequence of A007691.
%K nonn
%O 1,1
%A _Antti Karttunen_, May 21 2019
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