A146423 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1010-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 29, 29, 229, 229, 1773, 1773, 39925, 39925, 1086663, 1086663, 55544427, 55544427, 4442151653, 4442151653

Offset

1,9

Links

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

Example

Maximal 9 X 9 example
.1.1.1.1.0.1.1.1.1
.1.0.1.0.0.0.1.0.1
.0.1.0.1.0.1.0.1.0
.1.1.1.1.0.1.1.1.1
.0.0.0.0.0.0.0.0.0
.1.1.1.1.0.1.1.1.1
.0.1.0.1.0.1.0.1.0
.1.0.1.0.0.0.1.0.1
.1.1.1.1.0.1.1.1.1

Crossrefs

Sequence in context: A040813 A022363 A146226 * A146129 A146040 A146017

Adjacent sequences: A146420 A146421 A146422 * A146424 A146425 A146426

Keyword

nonn

Author

R. H. Hardin

Status

approved