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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..15.

CROSSREFS

Sequence in context: A037117 A283883 A173053 * A172013 A143781 A114077

Adjacent sequences:  A180390 A180391 A180392 * A180394 A180395 A180396

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 01 2010

STATUS

approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)