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G.f. is the polynomial (1-x^3) * (1-x^6) * (1-x^9) * (1-x^12) * (1-x^15) * (1-x^18) * (1-x^21) * (1-x^24) * (1-x^27) * (1-x^30) * (1-x^33) / (1-x)^11.
1

%I #9 Sep 08 2022 08:45:46

%S 1,11,66,285,990,2937,7721,18436,40689,84084,164307,305955,546260,

%T 939862,1564782,2529737,3982924,6122379,9207990,13575210,19650477,

%U 27968304,39189954,54123564,73745529,99222903,131936520,173504485

%N G.f. is the polynomial (1-x^3) * (1-x^6) * (1-x^9) * (1-x^12) * (1-x^15) * (1-x^18) * (1-x^21) * (1-x^24) * (1-x^27) * (1-x^30) * (1-x^33) / (1-x)^11.

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

%H G. C. Greubel, <a href="/A162628/b162628.txt">Table of n, a(n) for n = 0..187</a>

%t CoefficientList[ Series[Times @@ (1 - x^(3 Range@11))/(1 - x)^11, {x, 0, 70}], x] (* _G. C. Greubel_, Jul 06 2018 and slightly modified by _Robert G. Wilson v_, Jul 23 2018 *)

%o (PARI) x='x+O('x^50); Vec((1-x^3)*(1-x^6)*(1-x^9)*(1-x^12)*(1-x^15)*(1- x^18)*(1-x^21)*(1-x^24)*(1-x^27)*(1-x^30)*(1-x^33)/(1-x)^11) \\ _G. C. Greubel_, Jul 06 2018

%o (Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!((1-x^3)*(1-x^6)*(1-x^9)*(1-x^12)*(1-x^15)*(1- x^18)*(1-x^21)*(1-x^24)*(1-x^27)*(1-x^30)*(1-x^33)/(1-x)^11)); // _G. C. Greubel_, Jul 06 2018

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Dec 02 2009