A147133 - OEIS

A147133

Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1001-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 17, 17, 57, 57, 277, 277, 2295, 2295, 39117, 39117, 1059135, 1059135, 28274373

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OFFSET

1,9

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

Maximal 9 X 9 example

.0.0.0.0.0.0.0.0.0

.0.0.0.1.0.1.0.0.0

.1.0.0.1.0.1.0.0.1

.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

.1.0.0.1.0.1.0.0.1

.0.0.0.1.0.1.0.0.0

.0.0.0.0.0.0.0.0.0

CROSSREFS

Sequence in context: A146407 A146684 A146652 * A147164 A146692 A146439

Adjacent sequences: A147130 A147131 A147132 * A147134 A147135 A147136

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved