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%I #28 Jun 13 2015 00:52:02
%S 1,4,16,56,156,248,1584,2248,18512,51856,189440,609664,2023808,
%T 6579712,21441536,69575680,225665024,731127808,2367905792,7666302976,
%U 24816189440,80321511424,259955621888,841292972032,2722599796736
%N Expansion of -(9520*x^9 -11504*x^8 +2840*x^7 -1040*x^6 +248*x^5 +36*x^4 -1) / ((2*x -1)*(4*x^2 +2*x -1)).
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (4,0,-8).
%F G.f.: -(9520*x^9 -11504*x^8 +2840*x^7 -1040*x^6 +248*x^5 +36*x^4 -1) / ((2*x -1)*(4*x^2 +2*x -1)). - _Colin Barker_, Mar 15 2013
%F a(n) = +4*a(n-1) -8*a(n-3). - _Colin Barker_, Mar 15 2013
%t M0 = {{2, 2, 0}, {1, 0, 1}, {0, 2, 2}}; M1 = {{1, 0, 1}, {2, 2, 0}, {0, 2, 2}}; M2 = {{2, 2, 0}, {0, 2, 2}, {1, 0, 1}}; M[n_] := M[n] = If[Mod[v[n][[1]], 3] == 0, M1, If[Mod[v[n][[2]], 3] == 0, M0, M2]] v[0] = {1, 1, 1}; M[0] = {{2, 2, 0}, {0, 2, 2}, {1, 0, 1}}; v[n_] := v[n] = M[n - 1].v[n - 1] a0 = Table[v[n][[1]], {n, 0, 25}]
%K nonn,easy,less
%O 0,2
%A _Roger L. Bagula_, Mar 03 2006
%E Explicit name by _Joerg Arndt_, Mar 15 2013
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