, Volume 1, Issue 1, pp 49–54 | Cite as

Forests and score vectors

  • Daniel J. Kleitman
  • Kenneth J. Winston


Thescore vector of a labeled digraph is the vector of out-degrees of its vertices. LetG be a finite labeled undirected graph without loops, and let σ(G) be the set of distinct score vectors arising from all possible orientations ofG. Let ϕ(G) be the set of subgraphs ofG which are forests of labeled trees. We display a bijection between σ(G) and ϕ(G).

AMS subject classification (1980)

05 C 20 05 C 05 05 C 30 


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Copyright information

© Akadémiai Kiadó 1981

Authors and Affiliations

  • Daniel J. Kleitman
    • 1
  • Kenneth J. Winston
    • 1
  1. 1.Department of MathematicsMassachusetts Institute of TechnologyCambridgeUSA

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