A146403 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1111-0010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 7, 19, 47, 85, 259, 857, 3329, 13923, 76419, 375879, 2500865, 15196877, 126783213, 979497309, 10344645479, 100578970271

Offset

1,7

Links

Table of n, a(n) for n=1..22.

Example

Maximal 8 X 8 example
.1.1.0.0.0.0.0.1
.0.1.0.0.1.1.1.1
.0.1.1.0.0.1.0.0
.0.1.0.0.0.0.0.0
.0.0.0.0.0.0.1.0
.0.0.1.0.0.1.1.0
.1.1.1.1.0.0.1.0
.1.0.0.0.0.0.1.1

Crossrefs

Sequence in context: A143128 A238730 A139865 * A000491 A097039 A067651

Adjacent sequences: A146400 A146401 A146402 * A146404 A146405 A146406

Keyword

nonn

Author

R. H. Hardin

Status

approved