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%I #6 Oct 23 2017 22:21:43
%S 1,0,0,0,1,0,2,0,5,1,2,0,50,0,2,2,55,0,185,0,243,2,2,0,8903,1,2,19,
%T 1219,0,48824,0,5271,2,2,2,1323569,0,2,2,369182,0,1659512,0,36636,
%U 5111,2,0,254187394,1,53535,2,223502,0,65005979,2,16774462,2,2,0,235105418684,0,2,41386,47350055,2
%N Number of compositions (ordered partitions) of n into nontrivial divisors of n.
%H <a href="/index/Com#comp">Index entries for sequences related to compositions</a>
%F a(n) = [x^n] 1/(1 - Sum_{d|n, 1 < d < n} x^d).
%e a(8) = 5 because 8 has 4 divisors {1, 2, 4, 8} among which 2 are nontrivial divisors {2, 4} therefore we have [4, 4], [4, 2, 2], [2, 4, 2], [2, 2, 4] and [2, 2, 2, 2].
%t Table[d = Divisors[n]; Coefficient[Series[1/(1 - Sum[Boole[d[[k]] != 1 && d[[k]] != n] x^d[[k]], {k, Length[d]}]), {x, 0, n}], x, n], {n, 0, 65}]
%Y Cf. A027750, A070824, A100346, A293813, A293814, A294138.
%K nonn
%O 0,7
%A _Ilya Gutkovskiy_, Oct 23 2017