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%I #9 Mar 29 2024 14:07:01
%S 2,6,18,46,107,235,498,1032,2109,4273,8612,17302,34695,69495,139110,
%T 278356,556865,1113901,2227992,4456194,8912619,17825491,35651258,
%U 71302816,142605957,285212265,570424908,1140850222,2281700879
%N a(n) = T(n,2), array T as in A054134.
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (5,-9,7,-2).
%F G.f.: x^2(x^4-4x^3+6x^2-4x+2)/[(1-2x)(1-x)^3].
%t Drop[CoefficientList[Series[x^2(x^4-4x^3+6x^2-4x+2)/((1-2x)(1-x)^3),{x,0,30}],x],2] (* or *) LinearRecurrence[{5,-9,7,-2},{2,6,18,46,107},40] (* _Harvey P. Dale_, Mar 29 2024 *)
%Y Cf. A054134.
%K nonn,easy
%O 2,1
%A _Clark Kimberling_