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A331927 Number of compositions (ordered partitions) of n into distinct divisors of n. 3

%I

%S 1,1,1,1,1,1,7,1,1,1,1,1,31,1,1,1,1,1,31,1,25,1,1,1,895,1,1,1,121,1,

%T 151,1,1,1,1,1,1135,1,1,1,865,1,31,1,1,1,1,1,11935,1,1,1,1,1,151,1,

%U 841,1,1,1,129439,1,1,1,1,1,127,1,1,1,1

%N Number of compositions (ordered partitions) of n into distinct divisors of n.

%H <a href="/index/Com#comp">Index entries for sequences related to compositions</a>

%F a(n) = A331928(n) + 1 for n > 0.

%e a(6) = 7 because we have [6], [3, 2, 1], [3, 1, 2], [2, 3, 1], [2, 1, 3], [1, 3, 2] and [1, 2, 3].

%o (PARI) a(n)={if(n==0, 1, my(v=divisors(n)); subst(serlaplace(polcoef(prod(i=1, #v, 1 + y*x^v[i] + O(x*x^n)), n)), y, 1))} \\ _Andrew Howroyd_, Feb 01 2020

%Y Cf. A018818, A027750, A033630, A065205, A100346, A210442, A211111, A294138, A331928.

%K nonn

%O 0,7

%A _Ilya Gutkovskiy_, Feb 01 2020

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Last modified August 3 01:52 EDT 2021. Contains 346429 sequences. (Running on oeis4.)