A146613 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1111-0110 pattern in any orientation.

1, 1, 1, 1, 1, 7, 21, 49, 235, 1289, 9339, 82787, 865777, 11018603, 179905507, 3665014053, 93285011401, 2967105675995, 116229643915377, 5631229452463433

Offset

1,6

Links

Table of n, a(n) for n=1..20.

Example

Maximal 8 X 8 example
.0.0.0.0.1.1.0.0
.0.0.0.1.1.0.1.0
.0.0.0.1.1.0.1.1
.0.1.1.0.1.0.1.1
.1.1.1.1.0.1.1.0
.1.0.0.0.1.0.0.0
.0.1.1.1.1.0.0.0
.0.0.1.1.0.0.0.0

Crossrefs

Sequence in context: A146669 A146637 A146701 * A083012 A233329 A070313

Adjacent sequences: A146610 A146611 A146612 * A146614 A146615 A146616

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved