OFFSET
1,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (12,93,-576,-2592,5184,19440).
FORMULA
Let X = the Z/6Z addition table considered as a matrix: [0,1,2,3,4,5; 1,2,3,4,5,0; 2,3,4,5,0,1; 3,4,5,0,1,2; 4,5,0,1,2,3; 5,0,1,2,3,4]. a(n) = term (1,2) of X^n.
G.f.: -x*(216*x^4-468*x^3-78*x^2+28*x+1) / ((3*x+1)*(6*x-1)*(6*x+1)*(15*x-1)*(12*x^2-1)). - Colin Barker, May 25 2013
EXAMPLE
a(3) = 495 since term (1,2) of X^3 = 495.
MAPLE
a:= n-> (Matrix(6, (i, j)-> irem(i+j-2, 6))^n)[1, 2]:
seq(a(n), n=0..20); # Alois P. Heinz, May 25 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Gary W. Adamson and Roger L. Bagula, May 02 2008
EXTENSIONS
More terms from Colin Barker, May 25 2013
STATUS
approved