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A147173 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1111-0010-0010 pattern in any orientation. 0
1, 1, 1, 1, 1, 3, 11, 27, 57, 269, 1741, 11383, 71261, 614161, 7140843, 99666239, 1560593149, 29491532325, 702793762267, 20557975075647 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

Maximal 8 X 8 example

.0.0.0.0.0.0.1.0

.0.0.0.0.1.1.1.0

.0.0.0.0.0.0.1.0

.0.0.0.0.0.0.1.1

.0.1.0.0.0.0.0.0

.0.1.0.0.0.0.0.0

.1.1.1.1.0.0.0.0

.0.0.0.1.0.0.0.0

CROSSREFS

Sequence in context: A011941 A219621 A033960 * A147110 A147118 A147157

Adjacent sequences:  A147170 A147171 A147172 * A147174 A147175 A147176

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved

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Last modified November 30 08:19 EST 2021. Contains 349419 sequences. (Running on oeis4.)