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A180393
Number of permutations of 1..n with both permutation and its inverse having exactly 3 maxima.
0
0, 0, 0, 0, 3, 118, 1719, 15080, 96080, 489240, 2106564, 7954480, 27009063, 83965806, 242238695
OFFSET
1,5
CROSSREFS
Sequence in context: A037117 A283883 A173053 * A172013 A143781 A114077
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 01 2010
STATUS
approved