A257444 Number of (n+2) X (5+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 1 and no column sum 1.

65, 68, 77, 89, 107, 134, 173, 230, 314, 437, 617, 881, 1268, 1835, 2666, 3884, 5669, 8285, 12119, 17738, 25973, 38042, 55730, 81653, 119645, 175325, 256928, 376523, 551798, 808676, 1185149, 1736897, 2545523, 3730622, 5467469, 8012942, 11743514

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) + a(n-3) - a(n-4) for n>5.

Empirical g.f.: x*(65 - 62*x + 6*x^2 - 62*x^3 + 3*x^4) / ((1 - x)*(1 - x - x^3)). - Colin Barker, Dec 21 2018

Example

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

Crossrefs

Column 5 of A257447.

Sequence in context: A355313 A354474 A081647 * A045025 A321502 A095547

Adjacent sequences: A257441 A257442 A257443 * A257445 A257446 A257447

Keyword

nonn

Author

R. H. Hardin, Apr 23 2015

Status

approved