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A146155
Number of n X n binary arrays symmetric about main diagonal with all ones connected only either as two by three or three by two blocks.
0
1, 1, 1, 1, 3, 7, 14, 42, 163, 719, 3628, 22263, 164206, 1435593, 15071126, 189778079, 2837151684, 50511089269, 1077365551719, 27499985838212, 837318042012350, 30417349994865723, 1319974251781005014, 68432608866087524550
OFFSET
1,5
EXAMPLE
Maximal 8 X 8 example
.0.0.0.1.1.0.0.0
.0.0.0.1.1.0.0.0
.0.0.0.1.1.0.0.0
.1.1.1.0.0.0.1.1
.1.1.1.0.0.0.1.1
.0.0.0.0.0.0.1.1
.0.0.0.1.1.1.0.0
.0.0.0.1.1.1.0.0
CROSSREFS
Sequence in context: A184264 A298913 A266019 * A106363 A128658 A234042
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 27 2008
STATUS
approved