%I #10 Jul 20 2023 07:01:27
%S 0,0,0,1,0,1,0,2,1,1,0,3,0,1,1,3,0,3,0,3,1,1,0,5,0,1,2,3,0,4,0,4,1,1,
%T 1,6,0,1,1,5,0,4,0,3,3,1,0,7,1,2,1,3,0,5,1,5,1,1,0,8,0,1,3,5,1,4,0,3,
%U 1,4,0,9,0,1,2,3,1,4,0,7,3,1,0,8,1,1,1,5,0,8,1,3,1,1,0,9,0,3,3,5,0,4,0,5,4,1,0,9,0,4,0,7,0,4,1,3,3,1,0,12
%N Number of divisors of n that are in A175526.
%C Number of terms of A175526 that divide n.
%H Antti Karttunen, <a href="/A294904/b294904.txt">Table of n, a(n) for n = 1..25000</a>
%F a(n) = Sum_{d|n} (1-A294905(d)).
%F a(n) = 1 + (A294902(n)-A294905(n)).
%F a(n) + A294903(n) = A000005(n).
%t q[n_] := DivisorSum[n, DigitCount[#, 2, 1] &] > 2 * DigitCount[n, 2, 1]; a[n_] := DivisorSum[n, 1 &, q[#] &]; Array[a, 100] (* _Amiram Eldar_, Jul 20 2023 *)
%o (PARI)
%o A292257(n) = sumdiv(n,d,(d<n)*hammingweight(d));
%o A294905(n) = (A292257(n) <= hammingweight(n));
%o A294904(n) = sumdiv(n,d,(0==A294905(d)));
%Y Cf. A000120, A175526, A292257, A294901, A294902, A294903, A294905.
%Y Cf. also A294894.
%K nonn,base
%O 1,8
%A _Antti Karttunen_, Nov 10 2017
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