Iterative procedure for generating trees and directed trees
Wai‐Kai Chen · Electronics Letters · 1968
An iterative procedure for generating trees and directed trees is described. The procedure will not introduce any redundancies, duplications, or cancellations of terms, and is readily adaptable for a digital computer. With minor modifications, the process may also be used to generate 2-trees and directed 2-trees, and for the evaluation of the numbers of trees, directed trees, 2-trees and directed 2-trees efficiently.