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A220704
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Number of ways to reciprocally link elements of an n X n array either to themselves or to exactly two horizontal and antidiagonal neighbors, without consecutive collinear links
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1
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1, 1, 3, 13, 107, 1617, 44976, 2282408, 216083336, 37166744488, 11934907610044, 6974153590170208, 7595477025017870022, 15083748097547577433271, 55729708477784939752304144, 376141278066033748724918163244
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OFFSET
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1,3
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COMMENTS
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LINKS
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EXAMPLE
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All solutions for n=3 0=self 3=ne 4=w 6=e 7=sw (reciprocal directions total 10)
.00.00.00...00.67.47...00.00.00
.00.00.00...36.34.00...00.67.47
.00.00.00...00.00.00...36.34.00
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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