1 research outputs found
Hook Length Formulas for Trees by Han's Expansion
Recently Han obtained a general formula for the weight function corresponding
to the expansion of a generating function in terms of hook lengths of binary
trees. In this paper, we present formulas for k-ary trees, plane trees, plane
forests, labeled trees and forests. We also find appropriate generating
functions which lead to unifications of the hook length formulas due to Du and
Liu, Han, Gessel and Seo, and Postnikov.Comment: 16 page