✦ LIBER ✦

Expansion of Centered Triangulations

✍ Scribed by D. Benard; J.L. Fouquet

Publisher: Elsevier Science
Year: 1994
Tongue: English
Weight: 370 KB
Volume: 61
Category: Article
ISSN: 0095-8956
DOI: 10.1006/jctb.1994.1034

No coin nor oath required. For personal study only.

✦ Synopsis

We use a construction of A. Bouchet for covering triangulations by means of nowhere-zero dual flows, but slightly modified, to prove that whenever (G) is a simple graph, which is not a star, two-cell embedded in a surface (S), and (m) is a nonnegative integer not divisible by 2,3 , or 5 , there is a covering two-cell embedding of (G_{(m)}) in a surface (\tilde{S}), orientable if and only if (S) is orientable, such that each face of the embedding of (G) and the faces above it in the embedding of (G_{(m)}) have the same length. 1994 Academic Press, Inc.

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