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A146231
Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-1111 pattern in any orientation.
0
1, 1, 1, 5, 17, 35, 163, 959, 6943, 61513, 740733, 9820359, 193942865, 4360418313, 137513801459
OFFSET
1,4
EXAMPLE
Maximal 8 X 8 example
.1.1.0.0.1.1.1.1
.1.1.1.1.0.0.1.1
.0.0.0.0.0.0.0.0
.1.1.0.0.1.1.1.1
.1.1.1.1.0.0.1.1
.0.0.0.0.0.0.0.0
.1.1.0.0.1.1.1.1
.1.1.1.1.0.0.1.1
CROSSREFS
Sequence in context: A297520 A026394 A004538 * A186029 A083048 A123669
KEYWORD
nonn
AUTHOR
STATUS
approved