A146399 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1111-0010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 17, 17, 53, 53, 413, 413, 6359, 6359, 140181, 140181, 4762523, 4762523, 251128215, 251128215, 21398918375

Offset

1,9

Links

Table of n, a(n) for n=1..23.

Example

Maximal 9 X 9 example
.0.0.0.0.0.0.0.0.0
.1.0.0.0.0.0.0.0.1
.1.1.1.1.0.1.1.1.1
.0.0.1.0.0.0.1.0.0
.0.0.0.0.0.0.0.0.0
.0.0.1.0.0.0.1.0.0
.1.1.1.1.0.1.1.1.1
.1.0.0.0.0.0.0.0.1
.0.0.0.0.0.0.0.0.0

Crossrefs

Sequence in context: A146612 A146849 A146716 * A146407 A146684 A146652

Adjacent sequences: A146396 A146397 A146398 * A146400 A146401 A146402

Keyword

nonn

Author

R. H. Hardin

Status

approved