Graphs and Combinatorics

, Volume 3, Issue 1, pp 255–265 | Cite as

Some topics in cochromatic theory

  • John Gimbel
  • H. Joseph Straight


GivenG, a graph, the cochromatic number,Z(G), ofG is the fewest number of sets into which the vertex set can be partitioned so that each set induces a complete or an empty graph. A graph is critically cochromatic if the removal of any of its vertices decreases its cochromatic number. A graph is uniquely cochromatic if there is exactly one partition of minimum order in which each set induces a complete or an empty graph. A graph is comaximal if the removal of any edge increases its cochromatic number. These and related concepts are examined.


Related Concept Minimum Order Empty Graph 
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Copyright information

© Springer-Verlag 1987

Authors and Affiliations

  • John Gimbel
    • 1
  • H. Joseph Straight
    • 2
  1. 1.Colby CollegeWatervilleUSA
  2. 2.State University of New York at FredoniaFredoniaUSA

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