%I A123184
%S A123184 1,1,3,15,103,829,7131,62901,559897,4999879,44699763,399783639,
%T A123184 3576070333,31989586339,286166485929,2559950572641,22900519062931,
%U A123184 204861053422423,1832624941137951,16394109244633845,146656754883677131
%N A123184 A linear sum zero 9 X 9 matrix Markov: characteristic polynomial: (-3 
               + x)(-1 + x) x^3 (-1 + 3 x + 27 x^2 - 12 x^3 + x^4).
%C A123184 A Hadamard self-similar matrix of m: m={{1, -1, 0}, {-1, 2, -1}, {0, 
               -1, 1}}.{1,1,1}={0,0,0} 9 X 9 is: {{m,-m,0}, {-m,2*m-m}, {0,-m,m}} 
               A signed version of A011782 is an 6 X 6: {{-m,m}, {m,-m}}
%F A123184 M = {{-1, 1, 0, 1, -1, 0}, {1, -2, 1, -1, 2, -1}, {0, 1, -1, 0, -1, 1}, 
               {1, -1, 0, -1, 1, 0}, {-1, 2, -1, 1, -2, 1}, {0, -1, 1, 0, 1, -1}} 
               v[1] = {1, 0, 0, 0, 0, 1} v[n_] := v[n] = M.v[n - 1] a(n) = v[n][[1]]
%t A123184 M = {{-1, 1, 0, 1, -1, 0}, {1, -2, 1, -1, 2, -1}, {0, 1, -1, 0, -1, 1}, 
               {1, -1, 0, -1, 1, 0}, {-1, 2, -1, 1, -2, 1}, {0, -1, 1, 0, 1, -1}} 
               v[1] = {1, 0, 0, 0, 0, 1} v[n_] := v[n] = M.v[n - 1] a1 = Table[ 
               -v[n][[1]], {n, 1, 50}]
%Y A123184 Cf. A011782.
%Y A123184 Sequence in context: A152093 A109777 A135903 this_sequence A079486 A001274 
               A139766
%Y A123184 Adjacent sequences: A123181 A123182 A123183 this_sequence A123185 A123186 
               A123187
%K A123184 nonn,uned
%O A123184 1,3
%A A123184 Roger Bagula (rlbagulatftn(AT)yahoo.com), Oct 02 2006