منابع مشابه
Exact and asymptotic results on coarse Ricci curvature of graphs
Ricci curvature was proposed by Ollivier in a general framework of metric measure spaces, and it has been studied extensively in the context of graphs in recent years. In this paper we obtain the exact formulas for Ollivier’s Ricci-curvature for bipartite graphs and for the graphs with girth at least 5. These are the first formulas for Ricci-curvature that hold for a wide class of graphs, and e...
متن کاملAsymptotic Size Ramsey Results for Bipartite Graphs
We show that limn→∞ r̂(F1,n, . . . , Fq,n, Fp+1, . . . , Fr)/n exists, where the bipartite graphs Fq+1, . . . , Fr do not depend on n while, for 1 ≤ i ≤ q, Fi,n is obtained from some bipartite graph Fi with parts V1 ∪ V2 = V (Fi) by duplicating each vertex v ∈ V2 (cv + o(1))n times for some real cv > 0. In fact, the limit is the minimum of a certain mixed integer program. Using the Farkas Lemma ...
متن کاملOn (Kt-e)-Saturated Graphs
Given a graph H, we say a graph G is H-saturated if G does not contain H as a subgraph and the addition of any edge e′ 6∈ E(G) results in H as a subgraph. In this paper, we construct (K4 − e)-saturated graphs with |E(G)| either the size of a complete bipartite graph, a 3-partite graph, or in the interval [ 2n− 4, ⌊ n 2 ⌋ ⌈ n 2 ⌉ − n+ 6 ] . We then extend the (K4−e)-saturated graphs to (Kt − e)-...
متن کاملFurther Results on Betweenness Centrality of Graphs
Betweenness centrality is a distance-based invariant of graphs. In this paper, we use lexicographic product to compute betweenness centrality of some important classes of graphs. Finally, we pose some open problems related to this topic.
متن کاملOn Ramsey unsaturated and saturated graphs
A graph is Ramsey unsaturated if there exists a proper supergraph of the same order with the same Ramsey number, and Ramsey saturated otherwise. This has been studied by Balister, Lehel and Schelp [J. Graph Theory 51 (2006), 22–32]. In this paper, we show that some circulant graphs, trees with diameter 3, and Kt,n ∪ mK1 for infinitely many t, n and m, are Ramsey unsaturated.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1991
ISSN: 0012-365X
DOI: 10.1016/0012-365x(91)90140-w