Average length of the longest k-alternating subsequence

  title={Average length of the longest k-alternating subsequence},
  author={W. Cai},
  journal={J. Comb. Theory, Ser. A},
  • W. Cai
  • Published 5 February 2015
  • Computer Science, Mathematics
  • J. Comb. Theory, Ser. A
We prove a conjecture of Drew Armstrong on the average maximal length of k-alternating subsequence of permutations. The k = 1 case is a well-known result of Richard Stanley. 
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  • Report No. 12/2014,
  • 2014