A146877 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1110-0100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 13, 37, 65, 121, 421, 1309, 3649, 15177, 81237, 474405, 2569641, 13240801, 84039101, 586237485

Offset

1,8

Links

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

Example

Maximal 8 X 8 example
.1.0.0.0.0.1.1.1
.1.0.1.0.0.1.0.0
.1.1.1.0.1.1.1.0
.0.0.1.0.0.0.0.0
.0.0.0.0.0.1.0.0
.0.1.1.1.0.1.1.1
.0.0.1.0.0.1.0.1
.1.1.1.0.0.0.0.1

Crossrefs

Sequence in context: A118071 A307192 A147207 * A309720 A233435 A049742

Adjacent sequences: A146874 A146875 A146876 * A146878 A146879 A146880

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved