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A146041
Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 2X4 tee 1,1 1,2 1,3 2,3 1,4 in any orientation.
0
1, 1, 1, 1, 5, 21, 83, 385, 2131, 24025, 318135, 5078109, 98561015, 2403657061, 86079554793, 4029871316637, 240018399697859, 18147620162041911, 1762019890516576641, 229246937643264356069, 39291648711744977550585
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.0.1.1.1.1.0.0.0
.1.0.1.0.0.0.0.0
.1.1.0.1.1.1.1.0
.1.0.1.0.1.0.0.1
.1.0.1.1.0.0.0.1
.0.0.1.0.0.0.1.1
.0.0.1.0.0.1.0.1
.0.0.0.1.1.1.1.0
CROSSREFS
Sequence in context: A026017 A132310 A083319 * A146585 A351363 A215008
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 26 2008
STATUS
approved