A146003 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 3X3 plus 2,1 2,2 2,3 1,2 3,2.

1, 1, 2, 1, 2, 1, 7, 6, 19, 15, 82, 92, 528, 627, 4309, 6489, 53016, 91030, 867823, 1786877, 20390977, 49468143, 661574922, 1894696908, 30092058825, 102088443564, 1912895752719, 7656903764168, 169685780823556

Offset

1,3

Links

Table of n, a(n) for n=1..29.

Example

Maximal 8 X 8 example
.0.0.0.0.1.0.0.0
.0.0.0.1.1.1.0.0
.0.1.0.0.1.0.0.0
.1.1.1.0.0.0.1.0
.0.1.0.0.0.1.1.1
.0.0.0.1.0.0.1.0
.0.0.1.1.1.0.0.0
.0.0.0.1.0.0.0.0

Crossrefs

Sequence in context: A198316 A011128 A245595 * A334730 A201453 A260897

Adjacent sequences: A146000 A146001 A146002 * A146004 A146005 A146006

Keyword

nonn

Author

R. H. Hardin, Oct 26 2008

Status

approved