An infinite graph is 2-indivisible if the deletion of any finite set of vertices from the graph results in exactly one infinite component. Let G be a 4-connected, 2-indivisible, infinite, plane graph. It is known that G contains a spanning 1-way infinite path. In this paper, we prove a stronger resu
Spanning paths in infinite planar graphs
β Scribed by Dean, Nathaniel; Thomas, Robin; Yu, Xingxing
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 796 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Let G be a 4connected infinite planar graph such that the deletion of any finite set of vertices of G results in at most one infinite component. We prove a conjecture of Nash-Williams that G has a 1 -way infinite spanning path. 0 1996 John Wiley & Sons, Inc. [7] has shown that every 4-connected finite planar graph is hamiltonian. (In this paper graphs have no loops or multiple edges, but may be infinite.) To generalize Tutte's result to infinite graphs one can ask if every Cconnected infinite planar graph has a 1-way infinite spanning path, but that is clearly false. Indeed, no graph can have such a path if the deletion of some finite set of vertices leaves more than one infinite component. However, Nash-Williams [2] conjectured that this is the only way the generalization can fail. Nash-Williams' conjecture was partially confirmed by Jung [l] who proved it for triangulations. (Our thanks to R. Halin for bringing this reference to our attention.) We prove the conjecture in general, but we need some definitions before we can state our main result precisely.
INTRODUCTION
Tutte
π SIMILAR VOLUMES
Nash-Williams conjectured that a 4-connected infinite planar graph contains a spanning 2-way infinite path if, and only if, the deletion of any finite set of vertices results in at most two infinite components. In this article, we prove this conjecture for graphs with no dividing cycles and for grap
## Abstract Let __G__ be an infinite 4βconnected planar graph such that the deletion of any finite set of vertices from __G__ results in exactly one infinite component. Dean __et al__. proved that either __G__ admits a radial net or a special subgraph of __G__ admits a ladder net, and they used the
## Abstract A graph is __kβindivisible__, where __k__ is a positive integer, if the deletion of any finite set of vertices results in at most __k__ β 1 infinite components. In 1971, NashβWilliams conjectured that a 4βconnected infinite planar graph contains a spanning 2βway infinite path if and onl
This paper generalizes a theorem of Thomassen on paths in planar graphs. As a corollary, it is shown that every 4-connected planar graph has a Hamilton path between any two specified vertices x, y and containing any specified edge other than xy.
C. Thomassen extended Tutte's theorem on cycles in planar graphs in the paper "A Theorem on Paths in Planar Graphs". This note corrects a flaw in his proof.