A146876 - OEIS

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A146876

Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 1110-0100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 5, 17, 17, 37, 37, 81, 81, 581, 581

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

OFFSET

1,13

LINKS

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

EXAMPLE

Maximal 13 X 13 example

.0.0.0.1.0.0.0.0.0.1.0.0.0

.0.0.0.1.1.1.0.1.1.1.0.0.0

.0.0.0.1.0.1.0.1.0.1.0.0.0

.1.1.1.0.0.1.0.1.0.0.1.1.1

.0.1.0.0.0.0.0.0.0.0.0.1.0

.0.1.1.1.0.0.0.0.0.1.1.1.0

.0.0.0.0.0.0.0.0.0.0.0.0.0

.0.1.1.1.0.0.0.0.0.1.1.1.0

.0.1.0.0.0.0.0.0.0.0.0.1.0

.1.1.1.0.0.1.0.1.0.0.1.1.1

.0.0.0.1.0.1.0.1.0.1.0.0.0

.0.0.0.1.1.1.0.1.1.1.0.0.0

.0.0.0.1.0.0.0.0.0.1.0.0.0

CROSSREFS

Sequence in context: A125256 A228564 A075684 * A147206 A146852 A146237

Adjacent sequences: A146873 A146874 A146875 * A146877 A146878 A146879

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved