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A322853

Number of compositions (ordered partitions) of n into pentagonal pyramidal numbers (A002411).

1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 9, 12, 16, 21, 27, 34, 44, 57, 74, 96, 124, 159, 205, 265, 343, 444, 574, 740, 954, 1231, 1590, 2055, 2656, 3430, 4428, 5716, 7380, 9531, 12312, 15902, 20536, 26518, 34242, 44218, 57106, 73751, 95245, 122999, 158837, 205117

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OFFSET

0,7

LINKS

Table of n, a(n) for n=0..51.

Eric Weisstein's World of Mathematics, Pentagonal Pyramidal Number

Index entries for sequences related to compositions

FORMULA

G.f.: 1/(1 - Sum_{k>=1} x^(k^2*(k+1)/2)).

MATHEMATICA

nmax = 51; CoefficientList[Series[1/(1 - Sum[x^(k^2 (k + 1)/2), {k, 1, nmax}]), {x, 0, nmax}], x]

CROSSREFS