A146456 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1100-0111-0010 pattern in any orientation.

1, 1, 1, 1, 3, 11, 31, 113, 699, 5221, 45431, 522967, 8016431, 151899461, 3697922071, 116129380717, 4687373528579, 240290198107395, 15846179275453485, 1336337926181858025

Offset

1,5

Links

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

Example

Maximal 8 X 8 example
.0.1.1.0.0.0.0.0
.1.0.1.1.1.0.0.0
.1.1.0.1.0.0.0.0
.0.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.0
.0.0.0.0.1.0.1.1
.0.0.0.1.1.1.0.1
.0.0.0.0.0.1.1.0

Crossrefs

Sequence in context: A119901 A106934 A146581 * A095692 A163421 A173381

Adjacent sequences: A146453 A146454 A146455 * A146457 A146458 A146459

Keyword

nonn

Author

R. H. Hardin

Status

approved