✦ LIBER ✦

A retraction problem in graph theory

✍ Scribed by Alain Quilliot

Publisher: Elsevier Science
Year: 1985
Tongue: English
Weight: 563 KB
Volume: 54
Category: Article
ISSN: 0012-365X
DOI: 10.1016/0012-365x(85)90062-7

No coin nor oath required. For personal study only.

✦ Synopsis

Given two graphs G=(X,E), H=(Y,F); If AcX and if f is a function from A to Y, we pose the problem of deciding if f can be extended into a homomorphism from G to H. We know how to solve this problem when H is, for instance, a tree, or a chordal graph. We give here a solution to this problem when g is a planar graph and H is a cycle of G; The solution involves homotopy techniques.

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