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A146183
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 110-111-100 pattern in any orientation.
0
1, 1, 1, 1, 5, 17, 43, 197, 1293, 11263, 110807, 1310257, 21564593, 459131585, 12523288493, 440243859565, 19398701026043, 1090842898014815, 79649624560507867, 7542069381975617255, 913933732625520247505
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.0.0.1.1.1.0.0.0
.0.0.1.1.0.0.0.0
.1.1.0.1.0.0.0.0
.1.1.1.0.0.0.0.1
.1.0.0.0.0.1.1.1
.0.0.0.0.1.0.1.1
.0.0.0.0.1.1.0.0
.0.0.0.1.1.1.0.0
CROSSREFS
Sequence in context: A089527 A146778 A146858 * A163424 A294102 A190969
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 27 2008
STATUS
approved