Short, bijective proofs of identities for multisets of `hook pairs' (arm-leg pairs) of the cells of certain diagrams are given. These hook pair identities were originally foun...
In [5] the authors refine the well-known permutation statistic "descent" by fixing parity of one of the descent's numbers. In this paper, we generalize the results o...
Abstract. A leaf of a plane tree is called an old leaf if it is the leftmost child of its parent, and it is called a young leaf otherwise. In this paper we enumerate plane trees wi...
William Y. C. Chen, Emeric Deutsch, Sergi Elizalde