A079103 Catalan(n)^(2n-2).

1, 4, 625, 7529536, 9682651996416, 1605976966052654874624, 38858631894268190306056236008241, 149521802722388792654037601564900000000000000, 97507780747332761768395977098452480878573838263199129993216

Offset

1,2

Comments

For n >= 3, the number of permutations of length n(2n-1) in which all monotone subsequences of length n+1 are descending and the number of them is minimal.

Links

Table of n, a(n) for n=1..9.

Joseph Myers, The minimum number of monotone subsequences, Electronic J. Combin. 9(2) (2002), #R4.

Joseph Myers, The list for n=3

Mathematica

Table[CatalanNumber[n]^(2n-2), {n, 10}] (* Harvey P. Dale, Oct 24 2011 *)

Crossrefs

Cf. A079102, A079104, A079105, A079106.

Sequence in context: A210853 A232620 A219892 * A191953 A169619 A337650

Adjacent sequences: A079100 A079101 A079102 * A079104 A079105 A079106

Keyword

easy,nonn

Author

Joseph Myers, Dec 23 2002

Extensions

a(9) from Harvey P. Dale, Oct 24 2011

Status

approved