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A162680
G.f. is the polynomial (Product_{k=1..23} (1 - x^(3*k)))/(1-x)^23.
1
1, 23, 276, 2299, 14927, 80454, 374439, 1545807, 5771919, 19781035, 62936510, 187603065, 527817225, 1410264780, 3596907555, 8795685646, 20699124413, 47031284166, 103467710300, 220946372920, 458974273140, 929305397041
OFFSET
0,2
COMMENTS
This is a row of the triangle in A162499. Only finitely many terms are nonzero.
LINKS
MAPLE
m:=23: 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[23]))/(1-x)^23, {x, 0, 30}], x] (* Harvey P. Dale, Jun 04 2017 *)
PROG
(PARI) x='x+O('x^50); A = prod(k=1, 23, (1-x^(3*k)))/(1-x)^23; Vec(A) \\ G. C. Greubel, Jul 0762018
(Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); F:=(&*[(1-x^(3*k)): k in [1..23]])/(1-x)^23; Coefficients(R!(F)); // G. C. Greubel, Jul 06 2018
CROSSREFS
Sequence in context: A161523 A161930 A162365 * A010975 A022588 A268992
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 02 2009
STATUS
approved