A146743 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1110-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 13, 29, 57, 123, 437, 1523, 7643, 32273, 153925, 786845, 5340469, 36899655, 318800081, 2591600741, 26626203639, 272703572385

Offset

1,7

Links

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

Example

Maximal 8 X 8 example
.0.0.0.1.1.1.1.0
.1.0.0.1.1.1.0.0
.1.1.0.0.0.0.0.0
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.0.0.0.0.0.0.1.1
.0.0.1.1.1.0.0.1
.0.1.1.1.1.0.0.0

Crossrefs

Sequence in context: A098062 A094481 A045637 * A065546 A075636 A139838

Adjacent sequences: A146740 A146741 A146742 * A146744 A146745 A146746

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved