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A147257
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 0001-1101-0111 pattern in any orientation.
0
1, 1, 1, 1, 1, 5, 17, 39, 137, 661, 3965, 30475, 261877, 2593597, 32463645, 507974205, 9631596681, 224195557727, 6341197277447, 216685113312141, 8987183183859385
OFFSET
1,6
EXAMPLE
Maximal 8 X 8 example
.0.0.0.1.1.1.0.0
.0.0.0.1.0.0.1.0
.0.0.0.1.1.0.1.1
.1.1.1.0.1.0.0.1
.1.0.1.1.0.1.1.1
.1.0.0.0.1.0.0.0
.0.1.1.0.1.0.0.0
.0.0.1.1.1.0.0.0
CROSSREFS
Sequence in context: A250413 A163686 A147165 * A146645 A146717 A147467
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 04 2008
STATUS
approved