OFFSET
1,3
COMMENTS
A connected (0,1) matrix is one where you can get from any black square, i.e. 1, to any other by chess king moves.
REFERENCES
R. Levy and J. Shapiro, Uniqueness in paint-by-numbers puzzles, preprint, 2000.
LINKS
Index entries for linear recurrences with constant coefficients, signature (14,-52,26,-35).
FORMULA
a(n) = 14*a(n-1)-52*a(n-2)+26*a(n-3)-35*a(n-4). G.f.: -x^2*(3*x-1) / ((7*x-1)*(5*x^3-3*x^2+7*x-1)). - Colin Barker, Jan 13 2014
PROG
(PARI) Vec(-x^2*(3*x-1)/((7*x-1)*(5*x^3-3*x^2+7*x-1)) + O(x^100)) \\ Colin Barker, Jan 13 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, May 22 2000
EXTENSIONS
More terms from James A. Sellers, May 23 2000
More terms from Colin Barker, Jan 13 2014
STATUS
approved