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A180392 Number of permutations of 1..n with both permutation and its inverse having exactly 2 maxima 0
0, 0, 1, 12, 66, 248, 739, 1880, 4260, 8832, 17061, 31108, 54054, 90168, 145223, 226864 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..16.

CROSSREFS

Sequence in context: A271870 A114243 A000972 * A161805 A003200 A036399

Adjacent sequences:  A180389 A180390 A180391 * A180393 A180394 A180395

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 01 2010

STATUS

approved

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Last modified April 20 09:59 EDT 2019. Contains 322309 sequences. (Running on oeis4.)