A146464 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1100-0111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 7, 21, 55, 263, 1645, 13423, 126629, 1447199, 21743065, 415978809, 9965909653, 303132585251, 11591760284391, 555704916934105, 33613901189599473, 2574475177790739409

Offset

1,6

Links

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

Example

Maximal 8 X 8 example
.0.0.0.0.1.1.0.0
.0.0.1.1.1.0.0.0
.0.1.0.0.1.0.0.1
.0.1.0.0.0.1.1.1
.1.1.1.0.0.0.1.0
.1.0.0.1.0.0.1.0
.0.0.0.1.1.1.0.0
.0.0.1.1.0.0.0.0

Crossrefs

Sequence in context: A146400 A146408 A050894 * A001354 A200930 A088656

Adjacent sequences: A146461 A146462 A146463 * A146465 A146466 A146467

Keyword

nonn

Author

R. H. Hardin

Status

approved