ArticleOriginal scientific text

Title

The directed path partition conjecture

Authors 1, 1, 2, 3, 4

Affiliations

  1. Department of Mathematical Sciences, University of South Africa, P.O. Box 392, Pretoria, 0001 South Africa
  2. Department of Mathematics, University of Swaziland, Private Bag 4, Kwaluseni, M 201, Swaziland
  3. Department of Mathematics, Computer Science and Physics, Converse College, Spartanburg, South Carolina 29302, USA
  4. 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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Pages:
331-343
Main language of publication
English
Received
2004-03-18
Accepted
2004-10-28
Published
2005
Exact and natural sciences