A146375 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 0100-1111-0100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 21, 9, 201, 25, 1634, 125, 22896, 1331, 494897, 18779, 18283376, 389231, 1000392247, 11969301, 84124514832, 573650431, 10424120801341, 41782304071, 1874244968782308, 4475707668912

Offset

1,9

Links

Table of n, a(n) for n=1..28.

Example

Maximal 9 X 9 example
.0.1.0.0.1.0.0.1.0
.1.1.1.0.1.0.1.1.1
.0.1.0.1.1.1.0.1.0
.0.1.0.0.1.0.0.1.0
.0.0.0.0.0.0.0.0.0
.0.1.0.0.1.0.0.1.0
.0.1.0.1.1.1.0.1.0
.1.1.1.0.1.0.1.1.1
.0.1.0.0.1.0.0.1.0

Crossrefs

Sequence in context: A337422 A040424 A220132 * A371096 A040423 A318648

Adjacent sequences: A146372 A146373 A146374 * A146376 A146377 A146378

Keyword

nonn

Author

R. H. Hardin

Status

approved