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A165960
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Number of permutations of length n without modular 3-sequences.
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5
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1, 1, 2, 3, 20, 100, 612, 4389, 35688, 325395, 3288490, 36489992, 441093864, 5770007009, 81213878830, 1223895060315, 19662509071056, 335472890422812, 6057979285535388, 115434096553014565, 2314691409652237700, 48723117262650147387, 1074208020519710570054
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OFFSET
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0,3
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COMMENTS
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Modular 3-sequences are of the following form: i,i+1,i+2, where arithmetic is modulo n.
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LINKS
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FORMULA
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EXAMPLE
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For n=3 the a(3) = 3 solutions are (0,2,1), (1,0,2) and (2,1,0).
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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