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Directed star decompositions of the complete directed graph

✍ Scribed by Charles J. Colbourn; D. G. Hoffman; C. A. Rodger

Publisher: John Wiley and Sons
Year: 1992
Tongue: English
Weight: 545 KB
Volume: 16
Category: Article
ISSN: 0364-9024
DOI: 10.1002/jgt.3190160511

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✦ Synopsis

Abstract

An (s, t)‐directed star is a directed graph with s + t + 1 vertices and s + t arcs; s vertices have indegree zero and outdegree one, t have indegree one and outdegree zero, and one has indegree s and outdegree t. An (s, t)‐directed star decomposition is a partition of the arcs of a complete directed graph of order n into (s, t)‐directed starsx. We establish necessary and sufficient conditions on s, t, and n for an (s, t)‐directed star decomposition of order n to exist.

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