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%I #11 Sep 08 2022 08:45:46
%S 1,31,496,5455,46345,324136,1942335,10249065,48578364,209961884,
%T 837318680,3110233844,10844253964,35718892168,111747443068,
%U 333597393565,954069339889,2623073605414,6953911464088,17823614247238,44273067884650
%N G.f. is the polynomial (Product_{k=1..31} (1 - x^(3*k)))/(1-x)^31.
%C This is a row of the triangle in A162499. Only finitely many terms are nonzero.
%H G. C. Greubel, <a href="/A162737/b162737.txt">Table of n, a(n) for n = 0..1457</a>
%p m:=31: seq(coeff(series(mul((1-x^(3*i)),i=1..m)/(1-x)^m, x,n+1),x,n),n=0..21); # _Muniru A Asiru_, Jul 07 2018
%t CoefficientList[Series[Times@@(1-x^(3*Range[31]))/(1-x)^31, {x, 0, 50}], x] (* _G. C. Greubel_, Jul 07 2018 *)
%o (PARI) x='x+O('x^50); A = prod(k=1, 31, (1-x^(3*k)))/(1-x)^31; Vec(A) \\ _G. C. Greubel_, Jul 07 2018
%o (Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); F:=(&*[(1-x^(3*k)): k in [1..31]])/(1-x)^31; Coefficients(R!(F)); // _G. C. Greubel_, Jul 07 2018
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Dec 02 2009