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%I #7 Oct 01 2023 13:29:25
%S 1,2,6,9,18,54,81,162,486,729,1458,4374,6561,13122,39366,59049,118098,
%T 354294,531441,1062882,3188646,4782969,9565938,28697814,43046721,
%U 86093442,258280326,387420489,774840978,2324522934,3486784401,6973568802,20920706406,31381059609
%N Expansion of (1+2*x+6*x^2)/(1-9*x^3).
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 9).
%t CoefficientList[Series[(1 + 2*x + 6*x^2)/(1 - 9*x^3), {x, 0, 30}], x] (* _Wesley Ivan Hurt_, Sep 25 2021 *)
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Nov 11 2002