A147374 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 0111-1100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 5, 20, 29, 50, 83, 280, 625, 2242, 6281, 30765, 93559, 481174, 1596542, 9219820, 37372099, 265178423, 1263828408, 10782899831

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.0.1.0.0.1.1.1.0
.1.1.1.0.0.0.1.1
.1.0.1.0.1.1.1.0
.1.0.1.0.0.0.0.0
.0.0.0.0.0.1.0.1
.0.1.1.1.0.1.0.1
.1.1.0.0.0.1.1.1
.0.1.1.1.0.0.1.0

Crossrefs

Sequence in context: A360368 A088973 A005240 * A080654 A162690 A074219

Adjacent sequences: A147371 A147372 A147373 * A147375 A147376 A147377

Keyword

nonn

Author

R. H. Hardin

Status

approved