%I #21 Dec 26 2022 08:16:09
%S 0,1,1,1,1,1,2,4,0,8,12,4,40,72,24,352,640,192,4736,8704,2560,98816,
%T 181760,53760,3186688,5861376,1732608,158629888,291766272,86245376,
%U 12189433856,22419865600,6627262464,1445910806528,2659444588544
%N This sequence needs a meaningful name.
%t a = 1;
%t M1 = {{1, 0, 1}, {a, a, 0}, {a - 2, 1, a - 1}};
%t v[0] = {0, 1, 1}; v[1] = {1, 1, 1};
%t v[n_] := v[n] = MatrixPower[M1, n].v[n - 1];
%t b = Flatten[Table[v[n], {n, 0, 11}]]
%Y Cf. A103193.
%K nonn,uned,obsc,less
%O 0,7
%A _Roger L. Bagula_, Mar 18 2005