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A146153
Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only either as two by three or three by two blocks.
0
1, 1, 3, 3, 9, 11, 82, 254, 1669, 6665, 68316, 226521, 4561686, 23734103, 704383992, 5907579541, 236178663400, 2337315883467, 150056765859689, 1811327966926780, 189399759509400492, 3276661629995792339, 507766610202105772758
OFFSET
1,3
EXAMPLE
Maximal 8 X 8 example
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
.0.0.0.0.0.0.0.0
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
.0.0.0.0.0.0.0.0
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
CROSSREFS
Sequence in context: A124281 A351869 A320293 * A339028 A173048 A165992
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 27 2008
STATUS
approved