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%I #12 Jul 18 2015 11:09:23
%S 0,2,1,14,26,132,364,1416,4488,16016,53296,184736,625184,2145600,
%T 7303360,24979584,85196928,291057920,993379072,3392317952,11580678656,
%U 39541748736,134998297600,460924372992,1573671536640,5372896120832
%N Let M = {{0, -1, 2}, {-1, 2, -1}, {2, -1, 0}}; v[1] = {0, 0, 1}; v[n] = M.v[n - 1]; then a(n) = v[n][[1]]
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (2,6,-4).
%F a(n) = 2*a(n-1)+6*a(n-2)-4*a(n-3). G.f.: -x^2*(3*x-2)/((2*x+1)*(2*x^2-4*x+1)). [_Colin Barker_, Nov 08 2012]
%t M = {{0, -1, 2}, {-1, 2, -1}, {2, -1, 0}}; v[1] = {0, 0, 1}; v[n_] := v[n] = M.v[n - 1]; a1 = Table[v[n][[1]], {n, 1, 50}]
%t LinearRecurrence[{2,6,-4},{0,2,1},40] (* _Harvey P. Dale_, Jul 18 2015 *)
%K nonn,easy
%O 1,2
%A _Roger L. Bagula_ and _Gary W. Adamson_, Oct 31 2006
%E Edited by _N. J. A. Sloane_, Nov 04 2006