Another Enumeration of Trees
- 1 January 1968
- journal article
- Published by Canadian Mathematical Society in Canadian Journal of Mathematics
- Vol. 20, 1077-1086
- https://doi.org/10.4153/cjm-1968-104-8
Abstract
Given a set of vertices which have each been assigned one of the colours C1, C2, …, Cm, with nj vertices Cj, a formula is derived for the number of oriented trees on these vertices, having a designated root, and subject to any number of restrictions of the form “no arc goes from a vertex of colour Ci to a vertex of colour Cj”. The formula is based on a combinatorial construction which defines a correspondence between such trees and certain sequences.Keywords
This publication has 0 references indexed in Scilit: