A147388 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 10001-11111-00100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 6, 11, 18, 27, 65

Offset

1,9

Links

Table of n, a(n) for n=1..15.

Example

Maximal 9 X 9 example
.0.0.1.0.0.0.1.0.0
.0.0.1.1.1.1.1.0.0
.1.1.0.0.1.0.0.1.1
.0.1.0.0.0.0.0.1.0
.0.1.1.0.0.0.1.1.0
.0.1.0.0.0.0.0.1.0
.1.1.0.0.1.0.0.1.1
.0.0.1.1.1.1.1.0.0
.0.0.1.0.0.0.1.0.0

Crossrefs

Sequence in context: A157656 A059100 A131512 * A180712 A273225 A274621

Adjacent sequences: A147385 A147386 A147387 * A147389 A147390 A147391

Keyword

nonn

Author

R. H. Hardin

Status

approved