## Abstract A set __S__ of vertices is a determining set for a graph __G__ if every automorphism of __G__ is uniquely determined by its action on __S__. The determining number of __G__, denoted Det(__G__), is the size of a smallest determining set. This paper begins by proving that if __G__=__G__โกโ
On the crossing numbers of Cartesian products with trees
โ Scribed by Drago Bokal
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 204 KB
- Volume
- 56
- Category
- Article
- ISSN
- 0364-9024
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โฆ Synopsis
Abstract
Zip product was recently used in a note establishing the crossing number of the Cartesian product K~1~,n โก P~m~. In this article, we further investigate the relations of this graph operation with the crossing numbers of graphs. First, we use a refining of the embedding method bound for crossing numbers to weaken the connectivity condition under which the crossing number is additive for the zip product. Next, we deduce a general theorem for bounding the crossing numbers of (capped) Cartesian product of graphs with trees, which yields exact results under certain symmetry conditions. We apply this theorem to obtain exact and approximate results on crossing numbers of Cartesian product of various graphs with trees. ยฉ 2007 Wiley Periodicals, Inc. J Graph Theory 56: 287โ300, 2007
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