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A170815
Number of permutations of 1..n with all differences of elements separated by distances 1 through 9 being respectively unique.
0
1, 2, 4, 12, 40, 116, 200, 444, 760, 2160, 4368, 7852, 12828, 17252, 19612, 21104, 18276, 15096, 10240, 6464, 3776, 2536
OFFSET
1,2
COMMENTS
(Empirical) Equals A008404 for n<=2m+2, where m is the maximum difference separation 9.
CROSSREFS
Sequence in context: A180487 A000940 A008404 * A170814 A170813 A170812
KEYWORD
nonn
AUTHOR
R. H. Hardin Dec 02 2009
STATUS
approved