J. Korean Math. Soc. 2013; 50(3): 529-541
Printed May 1, 2013
https://doi.org/10.4134/JKMS.2013.50.3.529
Copyright © The Korean Mathematical Society.
Youngja Park and Seungkyung Park
Yonsei University, Yonsei University
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 \textit{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
MSC numbers: 05A15
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