A147227 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 11011-01110 pattern in any orientation.

1, 1, 1, 1, 1, 1, 2, 3, 6, 9, 16, 23, 72, 177, 631, 1684, 5696, 15819, 69884, 263612, 1492069, 6667995, 40872228, 203062570, 1480955534, 9070964673, 81908729534

Offset

1,7

Links

Table of n, a(n) for n=1..27.

Example

Maximal 8 X 8 example
.0.0.1.1.0.1.1.0
.0.0.0.1.1.1.0.1
.1.0.0.0.0.0.1.1
.1.1.0.0.0.0.1.0
.0.1.0.0.0.0.1.1
.1.1.0.0.0.0.0.1
.1.0.1.1.1.0.0.0
.0.1.1.0.1.1.0.0

Crossrefs

Sequence in context: A115995 A051057 A147364 * A147063 A357640 A007865

Adjacent sequences: A147224 A147225 A147226 * A147228 A147229 A147230

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved