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%I #29 Mar 11 2024 12:27:23
%S 6,12,18,20,24,28,36,40,48,56,80,88,96,100,104,112,160,176,192,196,
%T 200,204,208,220,224,260,264,272,304,320,336,352,368,384,392,416,448,
%U 464,496,544,550,580,608,640,648,650,672,704,736,768,784,832,896,928,992,1032,1040,1044,1056,1060,1068,1088,1104,1120,1184,1216
%N Numbers k such that A318468(k) (bitwise-AND of 2*k and sigma(k)) is equal to 2*k.
%C Positions of zeros in A324658, fixed points of A324659.
%C Intersection with A324649 gives A324643.
%C Intersection with A324726 gives A000396.
%C In the range 1..2^32 there are only 22 odd terms. See A324647.
%H Antti Karttunen, <a href="/A324652/b324652.txt">Table of n, a(n) for n = 1..20000</a>
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%t Select[Range[2000], 2*# == BitAnd[2*#, DivisorSigma[1, #]] &] (* _Paolo Xausa_, Mar 11 2024 *)
%o (PARI) for(n=1,oo,if((n+n)==bitand(2*n,sigma(n)), print1(n, ", ")))
%Y Cf. A000203, A191218, A318468, A324647, A324649, A324658, A324659, A324722, A324726.
%Y Some subsequences: A000396, A324643, A324647 (the odd terms).
%K nonn
%O 1,1
%A _Antti Karttunen_, Mar 14 2019