A147336 - OEIS

A147336

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 01000-11100-00111-00010 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 5, 17, 31, 53, 121, 345, 909

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OFFSET

1,9

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Maximal 9 X 9 example

.0.0.0.0.0.0.1.0.0

.0.1.0.0.0.1.1.1.0

.1.1.0.1.1.1.0.0.0

.0.1.1.0.1.0.1.0.0

.0.0.1.1.0.1.1.0.0

.0.0.1.0.1.0.1.1.0

.0.0.0.1.1.1.0.1.1

.0.1.1.1.0.0.0.1.0

.0.0.1.0.0.0.0.0.0

CROSSREFS

Sequence in context: A031013 A031370 A147434 * A128354 A078654 A083364

Adjacent sequences: A147333 A147334 A147335 * A147337 A147338 A147339

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved