Bijections for Refined Restricted Permutations Sergi Elizalde and Igor Pak
نویسندگان
چکیده
We present a bijection between 321and 132-avoiding permutations that preserves the number of fixed points and the number of excedances. This gives a simple combinatorial proof of recent results of Robertson, Saracino and Zeilberger [8], and the first author [3]. We also show that our bijection preserves additional statistics, which extends the previous results.
منابع مشابه
Bijections for refined restricted permutations
We present a bijection between 321and 132-avoiding permutations that preserves the number of fixed points and the number of excedances. This gives a simple combinatorial proof of recent results of Robertson et al. (Ann. Combin. 6 (2003) 427), and Elizalde (Proc. FPSAC 2003). We also show that our bijection preserves additional statistics, which extends the
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