This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A162602 #9 Sep 08 2022 08:45:46
%S A162602 1,9,45,164,486,1242,2837,5931,11538,21142,36828,61425,98657,153297,
%T A162602 231318,340035,488232,686268,946156,1281609,1708047,2242560,2903823,
%U A162602 3711960,4688355,5855409,7236243,8854348,10733184,12895731,15363997
%N A162602 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)^9.
%C A162602 This is a row of the triangle in A162499. Only finitely many terms are nonzero.
%H A162602 G. C. Greubel, <a href="/A162602/b162602.txt">Table of n, a(n) for n = 0..126</a>
%t A162602 CoefficientList[ Series[Times @@ (1 - x^(3 Range@9))/(1 - x)^9, {x, 0, 70}], x] (* _G. C. Greubel_, Jul 06 2018 and slightly modified by _Robert G. Wilson v_, Jul 23 2018 *)
%o A162602 (PARI) x='x+O('x^127); 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)^9) \\ _G. C. Greubel_, Jul 06 2018
%o A162602 (Magma) m:=127; 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)^9)); // _G. C. Greubel_, Jul 06 2018
%K A162602 nonn
%O A162602 0,2
%A A162602 _N. J. A. Sloane_, Dec 02 2009