L(2, 1)-Labelings of Some Families of Oriented Planar Graphs

Abstract

In this paper we determine, or give lower and upper bounds on, the 2-dipath and oriented L(2, 1)-span of the family of planar graphs, planar graphs with girth 5, 11, 16, partial k-trees, outerplanar graphs and cacti.

Keywords

• 2-dipath l(2
• 1)-labeling
• oriented l(2
• 1)-labeling
• homomorphism
• planar graph
• girth
• partial k-tree
• outerplanar graph
• cactus