A256804 Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 0 or 1 and no column sum 0 or 1

86, 312, 1167, 4219, 15291, 55798, 203129, 738760, 2689072, 9788263, 35621557, 129642381, 471844124, 1717266695, 6249942014, 22746670844, 82786372499, 301300009747, 1096578905535, 3990990415282, 14525173993491, 52864244476540

Offset

1,1

Comments

Column 2 of A256810

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = a(n-1) +4*a(n-2) +17*a(n-3) +18*a(n-4) -7*a(n-5) -37*a(n-6) -47*a(n-7) +2*a(n-8) +40*a(n-9) +21*a(n-10) -7*a(n-11) -3*a(n-12) -2*a(n-13) -a(n-14)

Example

Some solutions for n=4
..1..0..1..1....0..1..1..1....1..1..1..1....0..1..1..1....1..1..1..0
..1..1..1..1....1..1..0..1....1..1..1..1....1..1..1..1....1..1..1..1
..0..1..1..1....1..1..1..1....1..1..1..0....1..1..0..1....1..1..1..1
..1..1..1..0....0..1..1..1....1..1..0..1....1..1..1..1....1..1..0..1
..1..1..1..1....1..1..1..0....1..1..1..1....1..1..1..1....1..1..1..0
..1..1..1..1....1..1..0..1....1..0..1..1....1..1..1..0....1..0..1..1

Crossrefs

Cf. A256810

Sequence in context: A184086 A113690 A043379 * A368940 A162028 A157443

Adjacent sequences: A256801 A256802 A256803 * A256805 A256806 A256807

Keyword

nonn

Author

R. H. Hardin, Apr 10 2015

Status

approved