

A331928


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


2



1, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 30, 0, 0, 0, 0, 0, 30, 0, 24, 0, 0, 0, 894, 0, 0, 0, 120, 0, 150, 0, 0, 0, 0, 0, 1134, 0, 0, 0, 864, 0, 30, 0, 0, 0, 0, 0, 11934, 0, 0, 0, 0, 0, 150, 0, 840, 0, 0, 0, 129438, 0, 0, 0, 0, 0, 126, 0, 0, 0, 0
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OFFSET

0,7


LINKS

Table of n, a(n) for n=0..70.
Index entries for sequences related to compositions


FORMULA

a(n) = A331927(n)  1 for n > 0.


EXAMPLE

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


PROG

(PARI) a(n)={if(n==0, 1, my(v=divisors(n)); subst(serlaplace((0*y) + polcoef(prod(i=1, #v1, 1 + y*x^v[i] + O(x*x^n)), n)), y, 1))} \\ Andrew Howroyd, Feb 01 2020


CROSSREFS

Cf. A018818, A027751, A033630, A065205, A100346, A210442, A211111, A294138, A331927.
Sequence in context: A035322 A270031 A284105 * A228632 A229657 A306550
Adjacent sequences: A331925 A331926 A331927 * A331929 A331930 A331931


KEYWORD

nonn


AUTHOR

Ilya Gutkovskiy, Feb 01 2020


STATUS

approved



