A147487 - OEIS

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A147487

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 11011-01110-00100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 4, 7, 13, 21, 47, 71, 266, 697, 2575, 7222, 30644, 93493, 472633, 1837587, 10941522, 49363521, 346195883, 1801870833

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

OFFSET

1,7

LINKS

Table of n, a(n) for n=1..24.

EXAMPLE

Maximal 8 X 8 example

.1.0.0.1.1.0.1.1

.1.1.0.0.1.1.1.0

.0.1.1.0.0.1.0.0

.1.1.0.0.0.0.0.1

.1.0.0.0.0.0.1.1

.0.0.1.0.0.1.1.0

.0.1.1.1.0.0.1.1

.1.1.0.1.1.0.0.1

CROSSREFS

Sequence in context: A100848 A051458 A068940 * A190845 A190805 A008471

Adjacent sequences: A147484 A147485 A147486 * A147488 A147489 A147490

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved