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%I #17 Dec 04 2020 09:21:59
%S 0,0,1,0,1,0,1,0,2,0,1,0,1,2,3,0,1,0,1,0,1,2,1,0,2,2,3,3,1,2,1,0,2,0,
%T 3,0,1,2,2,0,1,0,1,3,5,2,1,0,2,2,3,3,1,2,2,4,2,2,1,0,1,2,3,0,3,0,1,0,
%U 2,4,1,0,1,2,4,3,3,2,1,0,3,2,1,0,3,2,3,4,1,4,3,0,3,2,3,0,1,4,4,3,1,2,1,4,4
%N a(n) is the number of such divisors d of n that A000120(d) does not divide n, where A000120(d) gives the binary weight of d.
%C Number of such positive integers k that divide n but A000120(k) [the Hamming weight of k] does not divide n.
%H Antti Karttunen, <a href="/A324393/b324393.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%F a(n) = Sum_{d|n} [A000120(d) does not divide n], where [ ] is the Iverson bracket.
%F a(n) = A000005(n) - A324392(n).
%F a(p) = 1 for all odd primes p.
%t a[n_] := DivisorSum[n, 1 &, !Divisible[n, DigitCount[#, 2, 1]] &]; Array[a, 100] (* _Amiram Eldar_, Dec 04 2020 *)
%o (PARI) A324393(n) = sumdiv(n, d, !!(n%hammingweight(d)));
%Y Cf. A000005, A000120, A324392, A306263 (positions of zeros).
%Y Cf. also A093653, A192895, A266342, A292257.
%K nonn,base
%O 1,9
%A _Antti Karttunen_, Mar 05 2019