A147322 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 00100-00100-00100-11111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 5, 9, 15, 23, 50, 117, 289, 741, 2046, 5466, 16079, 52199, 188773, 719705, 3000618

Offset

1,9

Links

Table of n, a(n) for n=1..25.

Example

Maximal 9 X 9 example
.0.0.1.1.1.1.1.0.0
.0.0.0.0.1.0.0.0.0
.1.0.0.0.1.0.0.0.1
.1.0.0.0.1.0.0.0.1
.1.1.1.1.0.1.1.1.1
.1.0.0.0.1.0.0.0.1
.1.0.0.0.1.0.0.0.1
.0.0.0.0.1.0.0.0.0
.0.0.1.1.1.1.1.0.0

Crossrefs

Sequence in context: A281704 A350607 A074693 * A143282 A323475 A097083

Adjacent sequences: A147319 A147320 A147321 * A147323 A147324 A147325

Keyword

nonn

Author

R. H. Hardin

Status

approved