Title of article :
On Gracefulness of Directed Trees with Short Diameters
Author/Authors :
Yao, Bing Northwest Normal University - College of Mathematics and Information Science, China , Yao, Ming Lanzhou Petrochemical College of Vocational Technology - Department of Information Process and Control Engineering, China , Cheng, Hui Northwest Normal University - College of Mathematics and Information Science, China
Abstract :
Graceful labelling is studied on undirected graphs since graceful graphs can be used in some H-decomposition problems. In this note, we inves-tigate the directed graceful problem for many orientations of undirected trees with short diameters, and provide some directed trees that deny any digraceful labelling.
Keywords :
Graceful labelling , dual labelling , digraceful labelling , tree , diameter.
Journal title :
Bulletin of the Malaysian Mathematical Sciences Society
Journal title :
Bulletin of the Malaysian Mathematical Sciences Society
