A147470 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1100-1111-0100-0100 pattern in any orientation.

1, 1, 1, 3, 5, 9, 19, 55, 245, 1021, 4107, 20679, 138093, 1077295, 9543083, 95957809, 1121795793, 15620825665, 256368054863, 4898555273539, 109719649027999, 2878513446258779, 87946594793312351

Offset

1,4

Links

Table of n, a(n) for n=1..23.

Example

Maximal 8 X 8 example
.0.0.1.0.0.0.1.1
.0.0.1.0.1.1.1.1
.1.1.1.1.0.0.1.0
.0.0.1.1.0.0.1.0
.0.1.0.0.1.1.0.0
.0.1.0.0.1.1.1.1
.1.1.1.1.0.1.0.0
.1.1.0.0.0.1.0.0

Crossrefs

Sequence in context: A227234 A192480 A107028 * A147010 A146912 A146940

Adjacent sequences: A147467 A147468 A147469 * A147471 A147472 A147473

Keyword

nonn

Author

R. H. Hardin

Status

approved