A147509 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 11110-01111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 5, 9, 15, 23, 53, 159, 467, 1455, 4183, 13257, 47381, 210539, 963601, 4871497, 24721415, 137844971, 829467103, 5811222331

Offset

1,8

Links

Table of n, a(n) for n=1..26.

Example

Maximal 8 X 8 example
.0.0.0.1.1.1.1.0
.0.0.1.1.1.1.0.1
.0.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.0
.1.0.1.1.1.1.0.0
.0.1.1.1.1.0.0.0

Crossrefs

Sequence in context: A033498 A147493 A178961 * A057259 A045599 A045604

Adjacent sequences: A147506 A147507 A147508 * A147510 A147511 A147512

Keyword

nonn

Author

R. H. Hardin

Status

approved