OFFSET
1,1
COMMENTS
If the starting vector {0,1,1,0} means the matrix 2 X 2 MA gives A zero points and B one point, them the permutation: p = {{0, 0, 0, 1}, {0, 0, 1, 0}, {0, 1, 0, 0}, {1, 0, 0, 0}}; reverses that to give {1,0,0,1}. This method makes the output of matrix MA the feed for MB and the output of MB the feed of MA as: M={{MA,0},{0,MB}}
FORMULA
M = {{0, 1, 0, 0}, {1, 1, 0, 0}, {0, 0, 1, 0}, {0, 0, 3, 1}}; v[1] = {0, 1, 1, 0}; p = {{0, 0, 0, 1}, {0, 0, 1, 0}, {0, 1, 0, 0}, {1, 0, 0, 0}} v[n_] := v[n] = p.M.v[n - 1] a(n) = Sum[v[n][[i]],{i,1,4}]
Conjecture: a(n) = 4*a(n-2)+a(n-4). G.f.: x*(x^3-2*x^2-6*x-2)/(x^4+4*x^2-1). [Colin Barker, Nov 01 2012]
MATHEMATICA
M = {{0, 1, 0, 0}, {1, 1, 0, 0}, {0, 0, 1, 0}, {0, 0, 3, 1}}; v[1] = {0, 1, 1, 0}; p = {{0, 0, 0, 1}, {0, 0, 1, 0}, {0, 1, 0, 0}, {1, 0, 0, 0}}; v[n_] := v[n] = p.M.v[n - 1]; a = Table[Apply[Plus, v[n]], {n, 1, 50}]
CROSSREFS
KEYWORD
nonn,uned
AUTHOR
Roger L. Bagula, Jan 10 2008
STATUS
approved