Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8898038 | Linear Algebra and its Applications | 2018 | 13 Pages |
Abstract
A signed graph GÏ consists of an underlying graph G and a sign function Ï, which assigns each edge uv of G a sign Ï(uv), either positive or negative. The adjacency matrix of GÏ is defined as A(GÏ)=(au,vÏ) with au,vÏ=Ï(uv)au,v, where au,v=1 if u,vâV(G) are adjacent, and au,v=0 otherwise. The positive inertia index of GÏ, written as p(GÏ), is defined to be the number of positive eigenvalues of A(GÏ). Recently, Yu et al. (2016) [12] characterized the signed graphs GÏ with pendant vertices such that p(GÏ)=2. In this paper, we extend the above work to a more general case, characterizing the signed graphs GÏ with cut points whose positive inertia index is 2.
Related Topics
Physical Sciences and Engineering
Mathematics
Algebra and Number Theory
Authors
Xinlei Wang, Dein Wong, Fenglei Tian,