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a(n) = 4694*a(n-2) + 9380*a(n-3) for n >= 3 with a(0) = 0 and a(1) = a(2) = 1.
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%I #56 Apr 11 2020 18:52:38

%S 0,1,1,4694,14074,22043016,110093076,103601931224,723540388824,

%T 487340138218336,4368084700020976,2294361417644038304,

%U 25075040078386453024,10810705128907312553856,139223348225447089786176,50980653751026190057165184,754918810679399231211479424

%N a(n) = 4694*a(n-2) + 9380*a(n-3) for n >= 3 with a(0) = 0 and a(1) = a(2) = 1.

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (0,4694,9380).

%F From _Colin Barker_, Jan 21 2013: (Start)

%F a(n) = 4694*a(n-2) + 9380*a(n-3) for n >= 3 with a(0) = 0 and a(1) = a(2) = 1.

%F G.f.: -x * (x + 1) / ((2*x + 1) * (4690*x^2 + 2*x - 1)). (End)

%p with(LinearAlgebra);

%p M := Matrix([[0, 1, 0], [0, 0, 1], [9380, 4694, 0]]);

%p w := proc(n) option remember;

%p if n = 0 then Matrix([[0], [1], [1]]); elif n >= 1 then

%p MatrixMatrixMultiply(M, w(n - 1)); end if;

%p end proc;

%p seq(w(n)[1, 1], n = 0..40); # _Petros Hadjicostas_, Nov 20 2019

%t M = {{0, 1, 0}, {0, 0, 1}, {9380, 4694, 0}};

%t w[0] = {{0}, {1}, {1}};

%t w[n_] := w[n] = M.w[n - 1];

%t a = Flatten[Table[w[n][[1]], {n, 0, 25}]]; (* Modified by _Petros Hadjicostas_, Nov 20 2019 *)

%t LinearRecurrence[{0,4694,9380},{0,1,1},20] (* _Harvey P. Dale_, Apr 11 2020 *)

%K nonn,less,easy

%O 0,4

%A _Roger L. Bagula_, Feb 16 2006

%E More terms from _Colin Barker_, Jan 21 2013

%E Edited and new name using formula from _Colin Barker_, _Joerg Arndt_, Nov 21 2019