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%I #13 Sep 18 2019 16:13:56
%S 1,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,0,
%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,1
%N Number of divisors d of n such that sigma(d)*d is equal to n.
%C a(n) tells how many times in total n occurs in A064987.
%H Antti Karttunen, <a href="/A327153/b327153.txt">Table of n, a(n) for n = 1..65537</a>
%F a(n) = Sum_{d|n} [A000203(d)*d == n], where [ ] is the Iverson bracket.
%e 336 has 20 divisors: [1, 2, 3, 4, 6, 7, 8, 12, 14, 16, 21, 24, 28, 42, 48, 56, 84, 112, 168, 336]. Only two of them, d=12 and d=14, satisfy sigma(d) = (336/d), thus a(336) = 2.
%o (PARI) A327153(n) = sumdiv(n, d, (n==d*sigma(d)));
%Y Cf. A000203, A064987, A327165 (positions of nonzero terms).
%Y Cf. also A324539.
%K nonn
%O 1,336
%A _Antti Karttunen_, Sep 18 2019
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