A146787 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0100-1100-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 5, 11, 21, 39, 105, 351, 1205, 4629, 16631, 70563, 335933, 1961161, 12194507, 84627809, 599408761

Offset

1,7

Links

Table of n, a(n) for n=1..22.

Example

Maximal 8 X 8 example
.0.0.0.1.1.1.1.0
.0.0.0.1.1.0.0.1
.0.0.0.0.1.0.0.1
.1.1.0.0.0.1.1.1
.1.1.1.0.0.0.1.1
.1.0.0.1.0.0.0.0
.1.0.0.1.1.0.0.0
.0.1.1.1.1.0.0.0

Crossrefs

Sequence in context: A298342 A293317 A230097 * A147243 A372451 A192664

Adjacent sequences: A146784 A146785 A146786 * A146788 A146789 A146790

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved