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%I #15 Dec 13 2023 08:32:01
%S 3,6,11,19,28,43,59,67,83,107,131,139,163,179,211,216,227,251,267,283,
%T 286,307,331,347,379,419,443,467,491,496,499,523,547,563,571,587,598,
%U 619,643,659,683,691,726,739,787,811,827,859,883,907,947,971,1019,1051,1091,1123,1163,1171,1187,1259,1283,1291,1307,1427,1451
%N Numbers k for which A087808(sigma(k)) is equal to A087808(2*k).
%C Conjecture: includes all terms of A007520. - _Bill McEachen_, Dec 10 2023
%H Antti Karttunen, <a href="/A332446/b332446.txt">Table of n, a(n) for n = 1..20751</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>
%o (PARI)
%o A087808(n) = if(n<1, 0, if(n%2==0, 2*A087808(n/2), A087808((n-1)/2)+1));
%o isA332446(n) = (A087808(2*n)==A087808(sigma(n)));
%Y Cf. A000203, A007520, A087808.
%Y Subsequences: A000396, A332445.
%Y Cf. A331751, A331752, A332208 for similar sequences.
%K nonn
%O 1,1
%A _Antti Karttunen_, Feb 14 2020
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