Dyck paths and restricted permutations
نویسندگان
چکیده
منابع مشابه
Dyck paths and restricted permutations
This paper is devoted to characterize permutations with forbidden patterns by using canonical reduced decompositions, which leads to bijections between Dyck paths and Sn(321) and Sn(231), respectively. We also discuss permutations in Sn avoiding two patterns, one of length 3 and the other of length k. These permutations produce a kind of discrete continuity between the Motzkin and the Catalan n...
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We exhibit a bijection between 132-avoiding permutations and Dyck paths. Using this bijection, it is shown that all the recently discovered results on generating functions for 132-avoiding permutations with a given number of occurrences of the pattern 12 . . . k follow directly from old results on the enumeration of Motzkin paths, among which is a continued fraction result due to Flajolet. As a...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2006
ISSN: 0166-218X
DOI: 10.1016/j.dam.2006.02.004