OFFSET
0,2
COMMENTS
This is a row of the triangle in A162499. Only finitely many terms are nonzero.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..672
MAPLE
m:=21: seq(coeff(series(mul((1-x^(3*k)), k=1..m)/(1-x)^m, x, n+1), x, n), n=0..21); # Muniru A Asiru, Jul 07 2018
MATHEMATICA
CoefficientList[Series[Times@@(1-x^(3*Range[21]))/(1-x)^21, {x, 0, 50}], x] (* G. C. Greubel, Jul 06 2018 *)
PROG
(PARI) x='x+O('x^50); A = prod(k=1, 21, (1-x^(3*k)))/(1-x)^21; Vec(A) \\ G. C. Greubel, Jul 06 2018
(Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); F:=(&*[(1-x^(3*k)): k in [1..21]])/(1-x)^21; Coefficients(R!(F)); // G. C. Greubel, Jul 06 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 02 2009
STATUS
approved