A146903 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 0010-1110-0111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 9, 9, 19, 19, 49, 49, 345, 345, 3029, 3029, 26343, 26343, 253497, 253497, 4034589, 4034589, 91237121, 91237121, 2505865849, 2505865849

Offset

1,9

Links

Table of n, a(n) for n=1..30.

Example

Maximal 9 X 9 example
.0.0.1.0.0.0.1.0.0
.1.1.1.0.0.0.1.1.1
.0.1.1.1.0.1.1.1.0
.0.1.0.0.0.0.0.1.0
.0.0.0.0.0.0.0.0.0
.0.1.0.0.0.0.0.1.0
.0.1.1.1.0.1.1.1.0
.1.1.1.0.0.0.1.1.1
.0.0.1.0.0.0.1.0.0

Crossrefs

Sequence in context: A147502 A147343 A147433 * A146607 A147072 A146068

Adjacent sequences: A146900 A146901 A146902 * A146904 A146905 A146906

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved