✦ LIBER ✦

Labeling angles of planar graphs

✍ Scribed by Feodor Loupekine; John J. Watkins

Publisher: Elsevier Science
Year: 1988
Tongue: English
Weight: 387 KB
Volume: 72
Category: Article
ISSN: 0012-365X
DOI: 10.1016/0012-365x(88)90214-2

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✦ Synopsis

A well-known theorem of Heawood states that 3-edge-coloring bridgeless planar cubic graphs-and, hence, the four-color theorem-is equivalent to labeling vertices with either +1 or -1 so that the sum around any face is 0 (mod 3). In this paper we introduce the notion of "angle-labeling" and give results analogous to Heawood's for bridgeless planar graphs with vertices of degree 2 or 3.

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