A146924 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0110-1111-0110 pattern in any orientation.

1, 1, 1, 1, 1, 5, 13, 32, 116, 329, 1343, 7578, 43263, 292424, 2337772, 20731810, 226646472, 2872512529, 41869404152, 707811350778, 14078518669729, 324770949354296

Offset

1,6

Links

Table of n, a(n) for n=1..22.

Example

Maximal 8 X 8 example
.0.0.0.1.1.0.0.0
.0.0.1.1.1.1.0.0
.0.1.0.1.1.0.1.0
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
.0.1.0.1.1.0.1.0
.0.0.1.1.1.1.0.0
.0.0.0.1.1.0.0.0

Crossrefs

Sequence in context: A272539 A066184 A231799 * A342032 A272161 A272828

Adjacent sequences: A146921 A146922 A146923 * A146925 A146926 A146927

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved