A258964 Number of (n+2) X (6+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.

1374, 951, 412, 503, 466, 694, 788, 952, 1004, 1684, 2354, 2767, 3218, 5695, 8618, 10027, 12074, 21739, 33674, 39067, 47498, 85915, 133898, 155227, 189194, 342619, 534794, 619867, 755978, 1369435, 2138378, 2478427, 3023114, 5476699, 8552714

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*(1374 + 951*x - 962*x^2 - 448*x^3 - 5442*x^4 - 3613*x^5 + 4170*x^6 + 2050*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..1..0..1..1..0..0..1....0..1..0..1..0..1..0..1....0..1..1..0..0..1..0..1
..0..1..1..0..0..1..1..0....1..0..0..1..1..0..0..1....1..0..0..1..1..0..0..1
..1..0..0..1..1..0..0..1....0..1..1..0..0..1..1..0....0..1..1..0..0..1..1..0
..0..1..1..0..0..1..1..0....1..0..0..1..1..0..0..1....1..0..0..1..1..0..0..1
..1..0..0..1..1..0..0..1....0..1..1..0..0..1..1..0....0..1..1..0..0..1..1..0
..0..1..1..0..1..0..1..0....1..0..1..0..1..0..1..0....0..0..1..0..1..0..1..0

Crossrefs

Column 6 of A258966.

Sequence in context: A168167 A069490 A239974 * A349235 A045131 A365868

Adjacent sequences: A258961 A258962 A258963 * A258965 A258966 A258967

Keyword

nonn

Author

R. H. Hardin, Jun 15 2015

Status

approved