A147458 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 11000-01111-11000 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 9, 21, 34, 61, 142, 363, 998, 3151, 10096, 34473, 121095, 493961, 2091176, 9966879, 48888970, 265507652

Offset

1,8

Links

Table of n, a(n) for n=1..24.

Example

Maximal 8 X 8 example
.0.0.0.1.1.0.1.0
.1.1.1.1.0.0.1.0
.0.0.0.1.1.0.1.0
.1.0.1.0.0.1.1.1
.1.1.1.0.0.1.0.1
.0.1.0.1.1.0.0.0
.0.1.0.0.1.1.1.1
.0.1.0.1.1.0.0.0

Crossrefs

Sequence in context: A286590 A061978 A031886 * A169927 A287057 A048780

Adjacent sequences: A147455 A147456 A147457 * A147459 A147460 A147461

Keyword

nonn

Author

R. H. Hardin

Status

approved