Journal of the Korean Mathematical Society (대한수학회지)

Korean Mathematical Society (대한수학회)
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AVOIDING PERMUTATIONS AND THE NARAYANA NUMBERS

  • Received : 2012.04.26
  • Published : 2013.05.01
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Abstract

We study 132 avoiding permutations that also avoid $(2r+1)(2r+2){\cdots}12$ but contain $(2r-1)(2r){\cdots}12$ pattern. We find an identity between the number of these permutations and the Narayana number. We also present relations between 132 avoiding permutations and polygon dissections. Finally, a generalization of these permutations is obtained.

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References

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