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a(n) = T(9,n), array T given by A048505.
2

%I #18 Jan 08 2023 14:46:08

%S 1,101,322,808,1872,4192,9232,20144,43696,94384,203184,436144,933808,

%T 1994672,4251568,9043888,19201968,40697776,86114224,181927856,

%U 383778736,808452016,1700790192,3573546928,7499415472,15720251312

%N a(n) = T(9,n), array T given by A048505.

%H Vincenzo Librandi, <a href="/A195855/b195855.txt">Table of n, a(n) for n = 0..2000</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (7,-18,20,-8).

%F a(n) = (n^2+37*n+324)*2^(n-2)-80.

%F a(n) = 7*a(n-1)-18*a(n-2)+20*a(n-3)-8*a(n-4). - _Colin Barker_, Feb 25 2015

%F G.f.: (352*x^3-367*x^2+94*x+1) / ((x-1)*(2*x-1)^3). _Colin Barker_, Feb 25 2015

%t LinearRecurrence[{7,-18,20,-8},{1,101,322,808},30] (* _Harvey P. Dale_, Jan 08 2023 *)

%o (Magma) [(n^2+37*n+324)*2^(n-2)-80: n in [0..30]]

%o (PARI) a(n)=(n^2+37*n+324)<<(n-2)-80 \\ _Charles R Greathouse IV_, Dec 27 2011

%o (PARI) Vec((352*x^3-367*x^2+94*x+1)/((x-1)*(2*x-1)^3) + O(x^100)) \\ _Colin Barker_, Feb 25 2015

%Y Cf. A048506, A048507, A048508, A048509, A048510, A048511, A048512, A048513, A048514, A048515.

%K nonn,easy

%O 0,2

%A _Vincenzo Librandi_, Sep 25 2011