A146862 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1101-0111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 17, 49, 273, 1285, 6059, 40935, 430893, 4529543, 70592583, 1153559653, 26967984571

Offset

1,6

Links

Table of n, a(n) for n=1..16.

Example

Maximal 8 X 8 example
.1.1.0.1.0.0.0.0
.0.1.1.1.0.0.1.1
.0.1.0.0.0.0.1.0
.1.0.0.0.0.1.1.1
.1.1.1.0.0.0.0.1
.0.1.0.0.0.0.1.0
.1.1.0.0.1.1.1.0
.0.0.0.0.1.0.1.1

Crossrefs

Sequence in context: A146855 A146666 A146730 * A146586 A146626 A146634

Adjacent sequences: A146859 A146860 A146861 * A146863 A146864 A146865

Keyword

nonn

Author

R. H. Hardin, Nov 04 2008

Status

approved