AVOIDING PERMUTATIONS AND THE NARAYANA NUMBERS

Title & Authors
AVOIDING PERMUTATIONS AND THE NARAYANA NUMBERS
Park, Youngja; Park, Seungkyung;

Abstract
We study 132 avoiding permutations that also avoid $\small{(2r+1)(2r+2){\cdots}12}$ but contain $\small{(2r-1)(2r){\cdots}12}$ 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.
Keywords
avoiding permutation;Narayana number;dissection number;
Language
English
Cited by
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