## Abstract In this article, we study a new product of graphs called __tight product__. A graph __H__ is said to be a tight product of two (undirected multi) graphs __G__~1~ and __G__~2~, if __V__(__H__) = __V__(__G__~1~) × __V__(__G__~2~) and both projection maps __V__(__H__)→__V__(__G__~1~) and _
Multimatroids III. Tightness and Fundamental Graphs
✍ Scribed by André Bouchet
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 323 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0195-6698
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✦ Synopsis
This paper continues the study of multimatroids. Here we introduce the subclass of tight multimatroids, which contains the liftings of even delta-matroids, the 3-matroids derived from isotropic systems, the Eulerian 3-matroids associated to 4-regular graphs and the Eulerian 2-matroids associated to evenly directed 4-regular graphs. The local properties of a tight multimatroid in the vicinity of a base are reflected by a fundamental graph, as in matroid theory. We describe how the fundamental graph is transformed when the base is modified. As an application we derive some connectivity properties of tight multimatroids.
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