A146427 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give

A146427

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1010-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 15, 29, 65, 155, 571, 2003, 10561, 41709, 230027, 1186171, 9353621, 63521901, 612736753, 4999574693, 59290750729, 622330543047

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,7

LINKS

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

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.0.1.1.0

.1.0.1.0.0.1.0.0

.1.1.1.1.0.1.1.0

.0.0.0.0.0.1.0.0

.0.0.1.0.0.0.0.0

.0.1.1.0.1.1.1.1

.0.0.1.0.0.1.0.1

.0.1.1.0.0.0.0.0

CROSSREFS

Sequence in context: A354161 A211324 A354163 * A202512 A014095 A192356

Adjacent sequences: A146424 A146425 A146426 * A146428 A146429 A146430

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved