For n points uniformly randomly distributed on the unit cube in d dimensions, ## Ε½ . with dG 2, let respectively, denote the minimum r at which the graph, obtained by n n adding an edge between each pair of points distant at most r apart, is k-connected Ε½ . w x respectively, has minimum degree k
On k-leaf connectivity of a random graph
β Scribed by Thomasz Luczak
- Publisher
- John Wiley and Sons
- Year
- 1988
- Tongue
- English
- Weight
- 367 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
We prove that, in a random graph with n vertices and N = cn log n edges, the subgraph generated by a set of all vertices of degree at least k + 1 is k-leaf connected for c > f . A threshold function for k-leaf connectivity is also found.
1. MAIN RESULTS
Let G = (V(G),E(G)) be a graph, where V ( G ) is its vertex set and E ( G ) denotes its set of edges. A graph G is k-leaf connected for some natural number k 2 2 if for every subset S C V ( G ) , IS1 = k , there exists a spanning tree of G such that S is the set of its endpoints. This concept was introduced by Murty as a generalization of hamiltonian connectivity (for recent results see [ 5 ] ) . Notice that 2-leaf connectivity is equivalent to the notion of hamiltonian connectivity, i.e., that every pair of vertices is joined by a hamiltonian path. Now let Kn,N denote a random graph with n vertices and N edges, where each of the ('2) possible graphs is equally likely.
We shall prove the following result:
The 2-leaf connectedness property (i.e., hamiltonian connectivity) of a random graph been considered by Bollobas [2], and recently by Bollobas. Fenner and Frieze [3], who proved Theorem 1 for the case k = 2 using an algorithmic approach.
π SIMILAR VOLUMES
## Abstract A graph is locally connected if for each vertex Ξ½ of degree __β§2__, the subgraph induced by the vertices adjacent to Ξ½ is connected. In this paper we establish a sharp threshold function for local connectivity. Specifically, if the probability of an edge of a labeled graph of order __n_
Given a connected graph G, denote by V the family of all the spanning trees of G. Define an adjacency relation in V as follows: the spanning trees t and t$ are said to be adjacent if for some vertex u # V, t&u is connected and coincides with t$&u. The resultant graph G is called the leaf graph of G.
While it is straightforward to simulate a very general class of random processes space-efficiently by non-unitary quantum computations (e.g., quantum computations that allow intermediate measurements to occur), it is not currently known to what extent restricting quantum computations to be unitary a
We prove that every n-connected graph G of sufficiently large order contains a connected graph H on four vertices such that G Γ V Γ°H Γ is Γ°n Γ 3Γ-connected. This had been conjectured in Mader (High connectivity keeping sets in n-connected graphs, Combinatorica, to appear). Furthermore, we prove uppe