## Abstract A homomorphism from an oriented graph __G__ to an oriented graph __H__ is a mapping $\varphi$ from the set of vertices of __G__ to the set of vertices of __H__ such that $\buildrel {\longrightarrow}\over {\varphi (u) \varphi (v)}$ is an arc in __H__ whenever $\buildrel {\longrightarrow}
Score sequences of oriented graphs
โ Scribed by Peter Avery
- Publisher
- John Wiley and Sons
- Year
- 1991
- Tongue
- English
- Weight
- 349 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
โฆ Synopsis
Abstract
We extend Landau's concept of the score structure of a tournament to that of the score sequence of an oriented graph, and give a condition for an arbitrary integer sequence to be a score sequence. The proof is by construction of a specific oriented graph ฮ(S) with given score sequence S. It is shown that ฮ(S) is transitive and has the minimum number of arcs among the oriented graphs with score sequence S.
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