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A195227
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Number of lower triangles of an n X n 0..3 array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by one or less
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1
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4, 22, 246, 5428, 237818, 20729610, 3601738548, 1249159521262, 865793424024974, 1200356073563114252, 3331551471246807302142, 18523112376180844925948966, 206425939461681776649215679048, 4613382950875473008207859661034814
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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Some solutions for n=4
..3........2........0........2........1........2........1........1
..3.2......3.2......1.1......1.2......1.0......2.3......1.0......0.1
..2.2.2....3.2.1....1.2.1....1.1.2....1.0.1....3.3.3....0.0.1....1.0.0
..3.2.3.3..2.2.2.1..2.2.2.1..1.2.1.1..1.0.1.2..3.3.2.3..1.0.1.0..1.0.0.1
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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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