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Number of permutations of length n containing the minimum number of monotone subsequences of length 4.
4

%I #3 Mar 30 2012 17:28:41

%S 1,2,6,22,86,306,882,1764,1764,8738,6892,1682,14706,4182,1250,6250,

%T 3750,1250

%N Number of permutations of length n containing the minimum number of monotone subsequences of length 4.

%C Conjectured to equal A079105 (and so have period 3) from a(17) onwards.

%H Joseph Myers, <a href="http://www.combinatorics.org/Volume_9/Abstracts/v9i2r4.html">The minimum number of monotone subsequences</a>, Electronic J. Combin. 9(2) (2002), #R4.

%Y Cf. A079102, A079103, A079105, A079106.

%K nonn

%O 1,2

%A _Joseph Myers_, Dec 23 2002