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A determinant sum sequence of the D5 dihehral 2 X 2 representation.
0

%I #4 Mar 12 2014 16:36:53

%S 0,1,1,2,3,5,8,13,21,34,55,2483,6053383,36651957891448,

%T 1343366154248994863013047386,

%U 1804632624381764689171354018874685160689875147803208124

%N A determinant sum sequence of the D5 dihehral 2 X 2 representation.

%D (*http : // mathworld.wolfram.com/DihedralGroupD3.html*)

%F << MathWorld`Groups` M0 = DihedralGroupMatrices[5]; s[n_] := M0[[n]] a[0] = Table[Fibonacci[n], {n, 0, 9}]; a[1] = Table[Fibonacci[n], {n,1, 10}]; a[n_] := a[n] = {a[n - 1][[2]], a[n - 1][[3]], a[n - 1][[4]], a[n - 1][[5]], a[n - 1][[6]], a[n - 1][[7]], a[n - 1][[8]], a[n - 1][[9]], a[n - 1][[10]], Abs[Det[Sum[a[n - 1][[i]]*s[i], {i, 1, 10}]]]}

%t Clear[a, f, s] (*http : // mathworld.wolfram.com/DihedralGroupD3.html*) << MathWorld`Groups` M0 = DihedralGroupMatrices[5]; s[n_] := M0[[n]] a[0] = Table[Fibonacci[n], {n, 0, 9}]; a[1] = Table[Fibonacci[n], {n, 1, 10}]; a[n_] := a[n] = {a[n - 1][[2]], a[n - 1][[3]], a[n - 1][[4]], a[n - 1][[5]], a[n - 1][[6]], a[n - 1][[7]], a[n - 1][[8]], a[n - 1][[9]], a[n - 1][[10]], Abs[Det[Sum[a[n - 1][[i]]*s[i], {i, 1, 10}]]]} Table[Floor[a[n][[1]]], {n, 0, 16}]

%Y Cf. A120495, A120496.

%K nonn,uned

%O 0,4

%A _Roger L. Bagula_, Aug 10 2006