A255152 Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 1 and no antidiagonal sum 1 and no row sum 0 or 1 and no column sum 0 or 1.

28, 62, 141, 331, 773, 1782, 4105, 9484, 21926, 50673, 117087, 270537, 625110, 1444437, 3337660, 7712270, 17820549, 41177539, 95148093, 219856758, 508018449, 1173867596, 2712431286, 6267558345, 14482316343, 33463986209, 77324534486

Offset

1,1

Links

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

Formula

Empirical: a(n) = 2*a(n-1) - a(n-2) + 3*a(n-3) + a(n-4) + 2*a(n-5) + 2*a(n-6).

Empirical g.f.: x*(28 + 6*x + 45*x^2 + 27*x^3 + 38*x^4 + 26*x^5) / (1 - 2*x + x^2 - 3*x^3 - x^4 - 2*x^5 - 2*x^6). - Colin Barker, Dec 18 2018

Example

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

Crossrefs

Column 1 of A255159.

Sequence in context: A336088 A255159 A071750 * A159652 A038641 A342756

Adjacent sequences: A255149 A255150 A255151 * A255153 A255154 A255155

Keyword

nonn

Author

R. H. Hardin, Feb 15 2015

Status

approved