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Spatial Graphs and Oriented Matroids: the Trefoil

✍ Scribed by J. L. Ramirez Alfonsin


Publisher
Springer
Year
1999
Tongue
English
Weight
165 KB
Volume
22
Category
Article
ISSN
0179-5376

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## 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}