Enumeration of edges in some lattices of paths
نویسندگان
چکیده
We enumerate the edges in the Hasse diagram of several lattices arising in the combinatorial context of lattice paths. Specifically, we consider the case of Dyck, Grand Dyck, Motzkin, Grand Motzkin, Schröder and Grand Schröder lattices. Finally, we give a general formula for the number of edges in an arbitrary Young lattice (which can be interpreted in a natural way as a lattice of paths). 1 Partially supported by PRIN project: “Automi e Linguaggi Formali: Aspetti Matematici e Applicativi”. 2 Partially supported by PRIN project: “Grafi e Combinatoria”.
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عنوان ژورنال:
- CoRR
دوره abs/1203.6792 شماره
صفحات -
تاریخ انتشار 2012