A146467 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-0111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 5, 23, 45, 89, 241, 909, 3431, 17195, 80847, 474101, 2777977, 19564237, 147127789, 1326666153, 12641403749, 144835493185

Offset

1,7

Links

Table of n, a(n) for n=1..22.

Example

Maximal 8 X 8 example
.0.0.0.0.0.1.1.0
.1.0.0.1.1.1.0.0
.1.1.1.0.0.1.0.0
.0.1.0.0.0.0.1.0
.0.1.0.0.0.0.1.0
.0.0.1.0.0.1.1.1
.0.0.1.1.1.0.0.1
.0.1.1.0.0.0.0.0

Crossrefs

Sequence in context: A293533 A121308 A222088 * A053518 A154625 A107011

Adjacent sequences: A146464 A146465 A146466 * A146468 A146469 A146470

Keyword

nonn

Author

R. H. Hardin

Status

approved