A147023 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 01000-11111-01000 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 3, 5, 11, 17, 29, 49, 194, 513, 1943, 5111, 18756, 56573, 304185, 1238797, 7708601, 34648607, 235404133, 1230092163, 10469480011, 68020491883

Offset

1,9

Links

Table of n, a(n) for n=1..28.

Example

Maximal 9 X 9 example
.0.0.0.0.0.1.0.0.0
.0.0.1.1.1.1.1.0.0
.0.1.0.0.0.1.0.1.0
.0.1.0.0.0.0.1.1.1
.0.1.0.0.0.0.0.1.0
.1.1.1.0.0.0.0.1.0
.0.1.0.1.0.0.0.1.0
.0.0.1.1.1.1.1.0.0
.0.0.0.1.0.0.0.0.0

Crossrefs

Sequence in context: A073022 A129694 A147015 * A108402 A090795 A087732

Adjacent sequences: A147020 A147021 A147022 * A147024 A147025 A147026

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved