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A300706 Number of compositions (ordered partitions) of n into squarefree parts that do not divide n. 4
1, 0, 0, 0, 0, 2, 0, 5, 2, 5, 2, 27, 2, 67, 12, 16, 28, 366, 4, 848, 28, 182, 153, 4591, 20, 4172, 554, 2217, 558, 57695, 6, 134118, 3834, 14629, 6972, 97478, 258, 1684852, 24467, 120869, 5308, 9104710, 189, 21165023, 124427, 117017, 297830, 114373157, 3394, 126979537, 72158, 7655405 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,6

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..2000

Index entries for sequences related to compositions

EXAMPLE

a(18) = 4 because we have [13, 5], [11, 7], [7, 11] and [5, 13].

MAPLE

with(numtheory):

a:= proc(m) option remember; local b; b:= proc(n) option

      remember; `if`(n=0, 1, add(`if`(not issqrfree(j) or

       irem(m, j)=0, 0, b(n-j)), j=2..n)) end; b(m)

    end:

seq(a(n), n=0..70);  # Alois P. Heinz, Mar 11 2018

MATHEMATICA

Table[SeriesCoefficient[1/(1 - Sum[Boole[Mod[n, k] != 0 && SquareFreeQ[k]] x^k, {k, 1, n}]), {x, 0, n}], {n, 0, 51}]

CROSSREFS

Cf. A005117, A280194, A284464, A300585, A300586, A300702, A300703, A300704.

Sequence in context: A267213 A261805 A300703 * A014842 A254708 A132816

Adjacent sequences:  A300703 A300704 A300705 * A300707 A300708 A300709

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Mar 11 2018

STATUS

approved

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Last modified April 5 06:13 EDT 2020. Contains 333238 sequences. (Running on oeis4.)