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%I #15 Mar 03 2020 08:56:09
%S 1,3,12,14,60,248,336,2160,2340,4064,13104,15120,16380,261888,1089270,
%T 4455360,8714160,10213632,11784960,16775168,22766400,45981824,
%U 71495424,98532480,229909120,689727360,738152448,4291822080,4294934528,5100118016,7091219520
%N Numbers m such that m divides sigma(2*m).
%C If m belongs to the sequence, then sigma(2*m)/m is an integer, so sigma(2*m)/(2*m) is either an integer or half of an integer, so 2*m is either perfect, multiperfect or hemiperfect. - _Michel Marcus_, Jul 09 2013
%H Jinyuan Wang, <a href="/A227302/b227302.txt">Table of n, a(n) for n = 1..54</a>
%o (PARI) is(n)=sigma(2*n)%n==0 \\ _Charles R Greathouse IV_, Nov 04 2016
%Y Cf. A000203, A000396, A007691, A159907, A232702.
%Y Cf. A141643, A055153, A141645, A159271, A160678. (hemiperfect numbers)
%K nonn
%O 1,2
%A _Alex Ratushnyak_, Jul 05 2013
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