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A165960
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Number of permutations of length n without modular 3-sequences
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4
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3, 20, 100, 612, 4389, 35688, 325395, 3288490, 36489992, 441093864, 5770007009, 81213878830
(list; graph; refs; listen; history; internal format)
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OFFSET
| 3,1
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COMMENTS
| Modular 3-sequences are of the following form: i,i+1,i+2, where arithmetic is modulo n.
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FORMULA
| Let b(n) be the sequence A165961. Then this sequence a(n)=n(b(n)).
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EXAMPLE
| For n=3 the a(3)=3 solutions are (0,2,1), (1,0,2) and (2,1,0).
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CROSSREFS
| Cf. A002628, A165961, A165962.
Sequence in context: A092786 A015529 A000948 * A074831 A203357 A000917
Adjacent sequences: A165957 A165958 A165959 * A165961 A165962 A165963
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KEYWORD
| nonn
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AUTHOR
| Isaac E. Lambert (lamberti09(AT)mail.wlu.edu), Oct 01 2009
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