A147102 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1000-1100-0111 pattern in any orientation.

1, 1, 1, 3, 7, 15, 33, 93, 429, 2069, 10289, 55429, 387995, 3482253, 35863559, 411870399, 5523860439, 89237334993, 1723598801687, 38814880673445, 1022726070574065

Offset

1,4

Links

Table of n, a(n) for n=1..21.

Example

Maximal 8 X 8 example
.0.1.1.1.0.0.0.1
.1.1.0.0.0.0.0.1
.1.0.0.0.0.0.1.1
.1.0.0.0.1.1.1.0
.0.0.0.1.0.0.0.1
.0.0.0.1.0.0.0.1
.0.0.1.1.0.0.1.1
.1.1.1.0.1.1.1.0

Crossrefs

Sequence in context: A211279 A351660 A199882 * A147379 A213722 A325924

Adjacent sequences: A147099 A147100 A147101 * A147103 A147104 A147105

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved