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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..24.

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: A147006 A146936 A184264 * A106363 A128658 A234042

Adjacent sequences:  A146152 A146153 A146154 * A146156 A146157 A146158

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 27 2008

STATUS

approved

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Last modified December 19 05:27 EST 2014. Contains 252177 sequences.