Let s(n) be the threshold for which each directed path of order smaller than s ( n ) is extendible from one of its endpoints in some tournament T,. It is shown that s(n) is asymptotic to 3n/4, with an error term at most 3 for infinitely many n. There are six tournaments with s ( n ) = n.
Paths extendable to cycles
β Scribed by T. D. Parsons
- Publisher
- John Wiley and Sons
- Year
- 1978
- Tongue
- English
- Weight
- 128 KB
- Volume
- 2
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Let k be a positive integer, and S a nonempty set of positive integers. Suppose that G is a connected graph containing a path of length k, and that each path P of length k in G is contained in some cycle C(P) of length s β S. We prove that every path of length less than k can be extended to a path of length k in G. This result answers conjectures of Entringer and Reid regarding when certain paths may be extended to cycles.
π SIMILAR VOLUMES
## Abstract A graph __G__ of order at least 2__n__+2 is said to be __n__βextendable if __G__ has a perfect matching and every set of __n__ independent edges extends to a perfect matching in __G__. We prove that every pair of nonadjacent vertices __x__ and __y__ in a connected __n__βextendable graph
## Abstract An Orthogonal Double Cover (ODC) of the complete graph __K__~__n__~ by an almostβhamiltonian cycle is a decomposition of 2__K__~__n__~ into cycles of length __n__β1 such that the intersection of any two of them is exactly one edge. We introduce a new class of such decompositions. If __n
## Abstract In 1960 Ore proved the following theorem: Let __G__ be a graph of order __n__. If __d__(__u__) + __d__(__v__)β₯__n__ for every pair of nonadjacent vertices __u__ and __v__, then __G__ is hamiltonian. Since then for several other graph properties similar sufficient degree conditions have
Given two integers n and k, n β₯ k > 1, a k-hypertournament T on n vertices is a pair (V, A), where V is a set of vertices, |V | = n and A is a set of k-tuples of vertices, called arcs, so that for any k-subset S of V, A contains exactly one of the k! k-tuples whose entries belong to S. A 2-hypertour