A258962 Number of (n+2) X (4+2) 0..1 arrays with no 3 X 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 0 or 3 and no column sum 0 or 3.

462, 467, 286, 312, 340, 503, 662, 761, 878, 1493, 2228, 2576, 3092, 5504, 8492, 9836, 11948, 21548, 33548, 38876, 47372, 85724, 133772, 155036, 189068, 342428, 534668, 619676, 755852, 1369244, 2138252, 2478236, 3022988, 5476508, 8552588, 9912476

Offset

1,1

Links

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

Formula

Empirical: a(n) = a(n-2) + 4*a(n-4) - 4*a(n-6) for n>12.

Empirical g.f.: x*(462 + 467*x - 176*x^2 - 155*x^3 - 1794*x^4 - 1677*x^5 + 1026*x^6 + 878*x^7 - 32*x^9 + 62*x^10 + 51*x^11) / ((1 - x)*(1 + x)*(1 - 2*x^2)*(1 + 2*x^2)). - Colin Barker, Dec 24 2018

Example

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

Crossrefs

Column 4 of A258966.

Sequence in context: A267404 A267343 A267396 * A267332 A353022 A104397

Adjacent sequences: A258959 A258960 A258961 * A258963 A258964 A258965

Keyword

nonn

Author

R. H. Hardin, Jun 15 2015

Status

approved