A147407 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1001-1001-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 5, 9, 21, 25, 109, 61, 921, 265, 6141, 2725, 55969, 40501, 883289, 485293, 21802429, 5980517, 645447537, 124941205

Offset

1,8

Links

Table of n, a(n) for n=1..25.

Example

Maximal 8 X 8 example
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.1.1.1.0.0.1.1.1
.0.0.1.0.0.1.0.0
.0.0.1.0.0.1.0.0
.1.1.1.0.0.1.1.1
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0

Crossrefs

Sequence in context: A255264 A321170 A328407 * A186297 A272986 A273642

Adjacent sequences: A147404 A147405 A147406 * A147408 A147409 A147410

Keyword

nonn

Author

R. H. Hardin

Status

approved