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A162638
G.f. is the polynomial (Product_{k=1..18} (1 - x^(3*k)))/(1-x)^18.
1
1, 18, 171, 1139, 5967, 26163, 99806, 340101, 1055070, 3022463, 8084196, 20366271, 48670438, 110977461, 242626770, 510702236, 1038606993, 2046949686, 3919950135, 7310939625, 13306606299, 23677953958, 41257164222, 70494485616
OFFSET
0,2
COMMENTS
This is a row of the triangle in A162499. Only finitely many terms are nonzero.
LINKS
MAPLE
m:=18: seq(coeff(series(mul((1-x^(3*k)), k=1..m)/(1-x)^m, x, n+1), x, n), n=0..23); # Muniru A Asiru, Jul 07 2018
MATHEMATICA
CoefficientList[Series[Times@@(1-x^(3*Range[18]))/(1-x)^18, {x, 0, 50}], x] (* G. C. Greubel, Jul 06 2018 *)
PROG
(PARI) x='x+O('x^50); A = prod(k=1, 18, (1-x^(3*k)))/(1-x)^18; Vec(A) \\ G. C. Greubel, Jul 06 2018
(Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); F:=(&*[(1-x^(3*k)): k in [1..18]])/(1-x)^18; Coefficients(R!(F)); // G. C. Greubel, Jul 06 2018
CROSSREFS
Sequence in context: A162346 A161878 A139618 * A010970 A126920 A341228
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 02 2009
STATUS
approved