A146589 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 0110-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 9, 25, 67, 353, 1577, 17635, 202483, 2019113, 31077783, 570196985, 14569116993, 519350763601, 19917427060103, 942336566340751, 58234146292140447, 4596656821240313323, 484270777652058510713

Offset

1,6

Links

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

Example

Maximal 8 X 8 example
.0.0.0.0.1.0.0.0
.0.0.0.1.1.1.0.0
.0.0.0.1.1.0.1.0
.0.1.1.0.1.0.1.1
.1.1.1.1.0.1.1.1
.0.1.0.0.1.0.1.0
.0.0.1.1.1.1.0.0
.0.0.0.1.1.0.0.0

Crossrefs

Sequence in context: A209530 A147392 A147318 * A146866 A271731 A126363

Adjacent sequences: A146586 A146587 A146588 * A146590 A146591 A146592

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved