%I #4 Mar 12 2014 16:36:53
%S 1,1,2,3,5,13,139,19136,366167031,134078294225149313,
%T 17976988982325707481237962186849833,
%U 323172132870659875927245721269598505772051876540063951439000722587455
%N A vector group determinant sequence in which the next element is made by a sum of the older elements over a vector like 2 X 2 matrix group.
%C This sequence type gets very large very fast.
%F s[1] = {{1, 0}, {0, 1}}; s[2] = {{1, 0}, {0, -1}}; s[3] = {{0, 1}, {1, 0}}; s[4] = {{0, 1}, {-1, 0}}; a[0] = {0, 1, 1, 2}; a[1] = {1, 1, 2, 3}; a[n_] := a[n] = {a[n - 1][[2]], a[n - 1][[3]], a[n - 1][[4]], Det[Sum[a[n - 1][[i]]*s[i], {i, 1, 4}]]} a(n)=a[n][[1]]
%t s[1] = {{1, 0}, {0, 1}}; s[2] = {{1, 0}, {0, -1}}; s[3] = {{0, 1}, {1, 0}}; s[4] = {{0, 1}, {-1, 0}}; a[0] = {0, 1, 1, 2}; a[1] = {1, 1, 2, 3}; a[n_] := a[n] = {a[n - 1][[2]], a[n - 1][[3]], a[n - 1][[4]], Det[Sum[a[n - 1][[i]]*s[i], {i, 1, 4}]]} Table[a[n][[1]], {n, 1, 15}]
%K nonn,uned
%O 0,3
%A _Roger L. Bagula_, Aug 06 2006
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