A147191 - OEIS

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A147191

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 11000-01110-00011 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 11, 21, 45, 95, 317, 775, 2631, 8089, 34521, 128479, 651913, 2804553, 16941209, 86096205, 609652687

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

OFFSET

1,8

LINKS

Table of n, a(n) for n=1..23.

EXAMPLE

Maximal 8 X 8 example

.1.0.0.0.0.0.1.1

.1.1.0.0.1.1.1.0

.0.1.0.1.1.0.0.0

.0.1.1.0.0.1.0.0

.0.0.1.0.0.1.1.0

.0.0.0.1.1.0.1.0

.0.1.1.1.0.0.1.1

.1.1.0.0.0.0.0.1

CROSSREFS

Sequence in context: A317298 A064568 A147073 * A327607 A034185 A184053

Adjacent sequences: A147188 A147189 A147190 * A147192 A147193 A147194

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved