A028075 - OEIS

%I #17 Sep 08 2022 08:44:50

%S 1,25,400,5230,60991,661675,6836950,68263360,664838581,6356961325,

%T 59947423900,559395635890,5177995501771,47632122760975,

%U 436056971109250,3977028159426820,36166503547714561,328145135909292625,2972035570568581000,26880644285129620150,242859379929646660951

%N Expansion of 1/((1-3x)(1-6x)(1-7x)(1-9x)).

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (25,-225,855,-1134).

%F a(n) = (2*9^(n+3) - 9*7^(n+3) + 8*6^(n+3) - 3^(n+3))/72. [_Yahia Kahloune_, Jun 10 2013]

%t CoefficientList[Series[1/((1-3x)(1-6x)(1-7x)(1-9x)),{x,0,20}],x] (* or *) LinearRecurrence[{25,-225,855,-1134},{1,25,400,5230},20] (* _Harvey P. Dale_, May 06 2018 *)

%o (Magma) [(2*9^(n+3)-9*7^(n+3)+8*6^(n+3)-3^(n+3))/72: n in [0..20]]; // _Vincenzo Librandi_, May 30 2019

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_