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A147175 Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 1000-1111-0010-0010 pattern in any orientation. 0
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 11, 11, 27, 27, 57, 57, 269, 269 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,13

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

Maximal 13 X 13 example

.0.0.0.0.1.0.0.0.1.0.0.0.0

.0.0.1.1.1.0.0.0.1.1.1.0.0

.0.1.0.0.1.0.0.0.1.0.0.1.0

.0.1.0.0.1.1.0.1.1.0.0.1.0

.1.1.1.1.0.0.0.0.0.1.1.1.1

.0.0.0.1.0.0.0.0.0.1.0.0.0

.0.0.0.0.0.0.0.0.0.0.0.0.0

.0.0.0.1.0.0.0.0.0.1.0.0.0

.1.1.1.1.0.0.0.0.0.1.1.1.1

.0.1.0.0.1.1.0.1.1.0.0.1.0

.0.1.0.0.1.0.0.0.1.0.0.1.0

.0.0.1.1.1.0.0.0.1.1.1.0.0

.0.0.0.0.1.0.0.0.1.0.0.0.0

CROSSREFS

Sequence in context: A318961 A309798 A068594 * A147112 A147120 A147159

Adjacent sequences:  A147172 A147173 A147174 * A147176 A147177 A147178

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified December 6 01:25 EST 2021. Contains 349558 sequences. (Running on oeis4.)