Every partition has, for some d, a Durfee square of side d. Every partition with Durfee square of side d gives rise to a "successive rank vector" r = (r1,
We construct a bijection between labeled trees and allowable pairs of permutations sorted by a priority queue. These are also the pairs of permutations that avoid the pattern pairs...
Let G be a simple graph with n( 2) vertices, and i(G) be the ith largest eigenvalue of G. In this paper we obtain the following: If 3(G) < 0, and there exists some index k, 2 ...
A defining set (of vertex coloring) of a graph G is a set of vertices S with an assignment of colors to its elements which has a unique completion to a proper coloring of G. We de...
Hossein Hajiabolhassan, Mojtaba L. Mehrabadi, Ruzb...
We say (n, e) (m, f), an (m, f) subgraph is forced, if every n-vertex graph of size e has an m-vertex spanned subgraph with f edges. For example, as Tur