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 A168502 For each permutation of {1,2,...,n} one or more integers might not be part of any longest increasing subsequence (LIS) of that permutation. The sequence lists the number of permutations for which ceiling(n/2) is not part of any LIS. For example, if n=4, 2 is not in any LIS of the two permutations (1342) and (3421). 4
 0, 0, 0, 2, 15, 122, 990, 9210, 91013, 1001285, 11774254, 150849588, 2059781391 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS The sequence lists the minimal term of members of the array n=1 {0} n=2 {0,0} n=3 {1,0,1} n=4 {6,2,2,6} n=5 {37,18,15,18,37} n=6 {257,153,122,122,153,257} n=7{1998,1338,1081,990,1081,1338,1998} n=8 {17280,12449,10298,9210,9210,10298,12449,17280}. The j-th row above lists the number of permutations on {1,2,...,j} for which 1,2,3,...,j are not part of any LIS. An alternative sequence would list the maximal terms in the rows above as 0,0,1,6,37,257,1998,17280,... LINKS A. Godbole, Publications (lists some related sequences) Manfred Scheucher, C Code CROSSREFS Cf. A167995, A167999. Sequence in context: A341929 A185758 A052448 * A127610 A085228 A341726 Adjacent sequences:  A168499 A168500 A168501 * A168503 A168504 A168505 KEYWORD nonn,more AUTHOR Anant Godbole, Brad Wild, Stephanie Goins, Nov 27 2009 EXTENSIONS a(9)-a(13) from Manfred Scheucher, Jun 08 2015 STATUS approved

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Last modified May 13 00:11 EDT 2021. Contains 343829 sequences. (Running on oeis4.)