A256747 Number of (n+2)X(7+2) 0..1 arrays with no 3x3 subblock diagonal sum 3 and no antidiagonal sum 3 and no row sum 0 and no column sum 0

31032, 28816, 38376, 33616, 96576, 155792, 404480, 615296, 1258112, 1664400, 5004928, 7111808, 19624576, 26821008, 65198848, 91451776, 279105152, 356736400, 1053470592, 1397940864, 3792784000, 5223606672, 16267412480, 19397621632

Offset

1,1

Comments

Column 7 of A256748

Links

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

Formula

Empirical: a(n) = -2*a(n-1) +2*a(n-2) +12*a(n-3) +17*a(n-4) -6*a(n-5) -2*a(n-6) +4*a(n-7) -144*a(n-8) -304*a(n-9) -96*a(n-10) +512*a(n-11) +512*a(n-12) for n>15

Example

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

Crossrefs

Cf. A256748

Sequence in context: A157111 A236976 A143162 * A090059 A234888 A151815

Adjacent sequences: A256744 A256745 A256746 * A256748 A256749 A256750

Keyword

nonn

Author

R. H. Hardin, Apr 09 2015

Status

approved