A255800 Number of (n+2) X (7+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 1 and no antidiagonal sum 2 and no row sum 0 and no column sum 3.

2380, 600, 329, 384, 472, 270, 344, 452, 447, 692, 832, 478, 624, 828, 831, 1308, 1552, 894, 1184, 1580, 1599, 2540, 2992, 1726, 2304, 3084, 3135, 5004, 5872, 3390, 4544, 6092, 6207, 9932, 11632, 6718, 9024, 12108, 12351, 19788, 23152, 13374, 17984

Offset

1,1

Links

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

Formula

Empirical: a(n) = 3*a(n-6) - 2*a(n-12) for n>15.

Empirical g.f.: x*(2380 + 600*x + 329*x^2 + 384*x^3 + 472*x^4 + 270*x^5 - 6796*x^6 - 1348*x^7 - 540*x^8 - 460*x^9 - 584*x^10 - 332*x^11 + 4352*x^12 + 672*x^13 + 148*x^14) / ((1 - x)*(1 + x)*(1 - x + x^2)*(1 + x + x^2)*(1 - 2*x^6)). - Colin Barker, Dec 20 2018

Example

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

Crossrefs

Column 7 of A255801.

Sequence in context: A226000 A163026 A069300 * A252469 A252420 A234818

Adjacent sequences: A255797 A255798 A255799 * A255801 A255802 A255803

Keyword

nonn

Author

R. H. Hardin, Mar 06 2015

Status

approved