Extending from bijections between marked occurrences of patterns to all occurrences of patterns
نویسندگان
چکیده
We consider two recent open problems stating that certain statistics on various sets of combinatorial objects are equidistributed. The first, posed by Anders Claesson and Svante Linusson, relates nestings in matchings on {1, 2, . . . , 2n} to occurrences of a certain pattern in permutations in Sn. The second, posed by Miles Jones and Jeffrey Remmel, relates occurrences of a large class of consecutive permutation patterns to occurrences of the same pattern in the cycles of permutations. We develop a general method that solves both of these problems and many more. We further employ the Garsia-Milne involution principle to obtain purely bijective proofs of these results. Résumé. Nous considérons deux dernières problèmes ouverts indiquant que certaines statistiques sur les divers ensembles d’objets combinatoires sont équiréparties. La première, posée par Anders Claesson et Svante Linusson, concerne les imbrications dans des filtrages sur {1, 2, . . . , 2n} pour les occurrences d’un certain modèle de permutations dans Sn. La seconde, posée par Miles Jones et Jeffrey Remmel, concerne les occurrences d’une large classe de schémas de permutation consécutive aux événements du même modèle dans les cycles de permutations. Nous développons une méthode générale qui résout ces deux problèmes et beaucoup plus. Nous avons également utiliser le principe d’involution Garsia-Milne pour obtenir des preuves purement bijective de ces résultats.
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تاریخ انتشار 2012