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A162639 G.f. is the polynomial  (Product_{k=1..19} (1 - x^(3*k)))/(1-x)^19. 1
1, 19, 190, 1329, 7296, 33459, 133265, 473366, 1528436, 4550899, 12635095, 33001366, 81671804, 192649265, 435276035, 945978271, 1984585264, 4031534950, 7951485085, 15262424710, 28569031009, 52246984967, 93504149189 (list; graph; refs; listen; history; text; internal format)
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..551

MAPLE

m:=19: seq(coeff(series(mul((1-x^(3*k)), k=1..m)/(1-x)^m, x, n+1), x, n), n=0..22); # Muniru A Asiru, Jul 07 2018

MATHEMATICA

CoefficientList[Series[Times@@(1-x^Range[3, 57, 3])/(1-x)^19, {x, 0, 30}], x] (* Harvey P. Dale, Apr 30 2018 *)

PROG

(PARI) x='x+O('x^50); A = prod(k=1, 19, (1-x^(3*k)))/(1-x)^19; Vec(A) \\ G. C. Greubel, Jul 06 2018

(MAGMA) m:=50; R<x>:=PowerSeriesRing(Integers(), m); F:=(&*[(1-x^(3*k)): k in [1..19]])/(1-x)^19; Coefficients(R!(F)); // G. C. Greubel, Jul 06 2018

CROSSREFS

Sequence in context: A176600 A139619 A121039 * A247614 A010971 A022584

Adjacent sequences:  A162636 A162637 A162638 * A162640 A162641 A162642

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Dec 02 2009

STATUS

approved

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Last modified October 19 03:54 EDT 2019. Contains 328211 sequences. (Running on oeis4.)