A147449 - OEIS

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A147449

Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 11000-01100-00110-00011 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 7, 7, 13, 13, 39, 39, 123, 123, 461, 461, 2371, 2371

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

OFFSET

1,13

LINKS

Table of n, a(n) for n=1..26.

EXAMPLE

Maximal 13 X 13 example

.0.0.1.0.0.0.0.0.0.0.1.0.0

.0.0.1.1.0.0.0.0.0.1.1.0.0

.1.1.0.1.1.0.0.0.1.1.0.1.1

.0.1.1.0.1.1.0.1.1.0.1.1.0

.0.0.1.1.0.1.0.1.0.1.1.0.0

.0.0.0.1.1.0.0.0.1.1.0.0.0

.0.0.0.0.0.0.0.0.0.0.0.0.0

.0.0.0.1.1.0.0.0.1.1.0.0.0

.0.0.1.1.0.1.0.1.0.1.1.0.0

.0.1.1.0.1.1.0.1.1.0.1.1.0

.1.1.0.1.1.0.0.0.1.1.0.1.1

.0.0.1.1.0.0.0.0.0.1.1.0.0

.0.0.1.0.0.0.0.0.0.0.1.0.0

CROSSREFS

Sequence in context: A126990 A128498 A146906 * A325344 A208474 A363979

Adjacent sequences: A147446 A147447 A147448 * A147450 A147451 A147452

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved