A162702 G.f. is the polynomial (Product_{k=1..25} (1 - x^(3*k)))/(1-x)^25.

1, 25, 325, 2924, 20450, 118430, 590849, 2609075, 10399220, 37970400, 128478090, 406588845, 1212516825, 3428709585, 9241809900, 23850595861, 59158506235, 141497700775, 327304605615, 734057883375, 1599785434275, 3394818382216

Offset

0,2

Comments

This is a row of the triangle in A162499. Only finitely many terms are nonzero.

The polynomial has degree 950. The polynomial is palindromic and all terms are nonzero. Hence, this sequence has 951 nonzero terms. - T. D. Noe, Apr 06 2011

Links

G. C. Greubel, Table of n, a(n) for n = 0..950

Maple

m:=25: 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@@Table[1-x^p, {p, 3, 75, 3}]/ (1-x)^25, {x, 0, 25}], x]  (* Harvey P. Dale, Apr 06 2011 *)

Prog

(PARI) x='x+O('x^50); A = prod(k=1, 25, (1-x^(3*k)))/(1-x)^25; Vec(A) \\ G. C. Greubel, Jul 06 2018
(Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); F:=(&*[(1-x^(3*k)): k in [1..25]])/(1-x)^25; Coefficients(R!(F)); // G. C. Greubel, Jul 06 2018

Crossrefs

Sequence in context: A188355 A243089 A079875 * A010977 A022589 A344656

Adjacent sequences: A162699 A162700 A162701 * A162703 A162704 A162705

Keyword

nonn

Author

N. J. A. Sloane, Dec 02 2009

Status

approved