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A331927 Number of compositions (ordered partitions) of n into distinct divisors of n. 3
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, 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, 841, 1, 1, 1, 129439, 1, 1, 1, 1, 1, 127, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

LINKS

Table of n, a(n) for n=0..70.

Index entries for sequences related to compositions

FORMULA

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

EXAMPLE

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].

PROG

(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

CROSSREFS

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

Sequence in context: A170824 A248909 A140213 * A285483 A284097 A091258

Adjacent sequences:  A331924 A331925 A331926 * A331928 A331929 A331930

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Feb 01 2020

STATUS

approved

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Last modified June 19 03:36 EDT 2021. Contains 345125 sequences. (Running on oeis4.)