A146939 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1111-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 8, 13, 24, 41, 98, 229, 673, 1711, 5548, 16018, 61606, 212821, 953199, 3714584, 18906725, 85353129, 504635142, 2652064148, 18219772927, 110274034707, 872419840249, 6103743292627, 55838534314788

Offset

1,7

Links

Table of n, a(n) for n=1..30.

Example

Maximal 8 X 8 example
.0.0.1.1.1.1.0.0
.0.0.1.1.1.1.0.0
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.1.1.0.0.0.0.1.1
.0.0.1.1.1.1.0.0
.0.0.1.1.1.1.0.0

Crossrefs

Sequence in context: A185954 A051838 A076792 * A181540 A059028 A066809

Adjacent sequences: A146936 A146937 A146938 * A146940 A146941 A146942

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved