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%I #4 Sep 24 2019 22:01:06
%S 1,1,1,1,5,1,13,1,34,19,89,1,927,1,610,189,4930,1,35890,1,46754,1873,
%T 28657,1,3919944,571,196418,18560,4205249,1,110187694,1,39882198,
%U 183916,9227465,9496,14484956252,1,63245986,1822473,11969319436,1,141930520462,1,34020543362,339200673
%N Number of compositions (ordered partitions) of n into divisors of n that are at most sqrt(n).
%F a(n) = [x^n] 1 / (1 - Sum_{d|n, d <= sqrt(n)} x^d).
%F a(p) = 1, where p is prime.
%t a[n_] := SeriesCoefficient[1/(1 - Sum[Boole[d <= Sqrt[n]] x^d, {d, Divisors[n]}]), {x, 0, n}]; Table[a[n], {n, 0, 45}]
%Y Cf. A100346, A294137, A294138, A327642.
%K nonn
%O 0,5
%A _Ilya Gutkovskiy_, Sep 24 2019
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