Given an infinite graph G, let deg,(G) be defined as the smallest d for which V(G) can be partitioned into finite subsets of (uniformly) bounded size such that each part is adjacent to at most d others. A countable graph G is constructed with de&(G) > 2 and with the property that [{y~V(G):d(x, y)sn}
On vertex k-partitions of certain infinite graphs
β Scribed by Douglas Cenzer; Edward Howorka
- Publisher
- Elsevier Science
- Year
- 1978
- Tongue
- English
- Weight
- 826 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
Let G be an infinite graph; define de& G to be the least m such that any partition P of the vertex set of G into sets of uniformly bounded cardinality contains a set which is adjacent to at least m Other sets of the partition. If G is either a regular tree 01 a triangtiisr, sqzart or hexagonal planar mosaic graph, it is shown that deg, G equals the degree of G. This verifies some conjectures of S. Ulam. Several open problems are given.
π SIMILAR VOLUMES
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