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Characterizing planarity using theta graphs

✍ Scribed by Archdeacon, Dan; S?r�n?, Josef


Publisher
John Wiley and Sons
Year
1998
Tongue
English
Weight
87 KB
Volume
27
Category
Article
ISSN
0364-9024

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✦ Synopsis


A theta graph is a homeomorph of K 2,3 . In an embedded planar graph the local rotation at one degree-three vertex of a theta graph determines the local rotation at the other degree-three vertex. Using this observation, we give a characterization of planar graphs in terms of balance in an associated signed graph whose vertices are K 1,3 subgraphs and whose edges correspond to theta graphs.


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