ArticleOriginal scientific text
Title
The directed path partition conjecture
Authors 1, 1, 2, 3, 4
Affiliations
- Department of Mathematical Sciences, University of South Africa, P.O. Box 392, Pretoria, 0001 South Africa
- Department of Mathematics, University of Swaziland, Private Bag 4, Kwaluseni, M 201, Swaziland
- Department of Mathematics, Computer Science and Physics, Converse College, Spartanburg, South Carolina 29302, USA
- Department of Mathematics and Statistics, University of Winnipeg, Manitoba R3B 2E9 Canada
Abstract
The Directed Path Partition Conjecture is the following: If D is a digraph that contains no path with more than λ vertices then, for every pair (a,b) of positive integers with λ = a+b, there exists a vertex partition (A,B) of D such that no path in D⟨A⟩ has more than a vertices and no path in D⟨B⟩ has more than b vertices. We develop methods for finding the desired partitions for various classes of digraphs.
Keywords
longest path, Path Partition Conjecture, vertex partition, digraph, prismatic colouring
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