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URL: https://oeis.org/A180394

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A180394
Number of permutations of 1..n with both permutation and its inverse having exactly 4 maxima.
0
0, 0, 0, 0, 0, 0, 19, 1784, 55092, 952640, 11346508, 103655440, 774656344, 4940080352, 27682462431
OFFSET
1,7
CROSSREFS
Sequence in context: A242564 A068748 A289736 * A220990 A098846 A116012
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 01 2010
STATUS
approved