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A147121 Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1000-1111-0100 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 7, 23, 49, 87, 207, 721, 2133, 8229, 34269, 162105, 830967, 4627991, 26390809, 175258607 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

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

EXAMPLE

Maximal 8 X 8 example

.1.0.0.0.0.1.1.1

.1.0.0.0.1.1.0.0

.1.1.1.1.0.1.0.0

.0.1.0.0.0.1.0.0

.0.0.1.0.0.0.1.0

.0.0.1.0.1.1.1.1

.0.0.1.1.0.0.0.1

.1.1.1.0.0.0.0.1

CROSSREFS

Sequence in context: A162290 A180044 A062725 * A098334 A038796 A211791

Adjacent sequences:  A147118 A147119 A147120 * A147122 A147123 A147124

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified December 11 04:17 EST 2016. Contains 279034 sequences.