A146709 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1100-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 7, 21, 51, 237, 1129, 8811, 85099, 859569, 10699439, 171553261, 3455226259, 90780787231, 2937046608631, 113622292506777, 5452353589454277, 328302441188610241

Offset

1,6

Links

Table of n, a(n) for n=1..21.

Example

Maximal 8 X 8 example
.0.0.1.1.0.0.0.0
.0.0.1.1.1.1.0.0
.1.1.0.1.0.0.1.0
.1.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.1
.0.1.0.0.1.0.1.1
.0.0.1.1.1.1.0.0
.0.0.0.0.1.1.0.0

Crossrefs

Sequence in context: A233329 A070313 A146733 * A146400 A146408 A050894

Adjacent sequences: A146706 A146707 A146708 * A146710 A146711 A146712

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved