Linial's Conjecture for Arc-spine Digraphs

Autor: Lucas Rigo Yoshimura, Orlando Lee, Maycon Sambinelli, Cândida Nunes da Silva
Rok vydání: 2019
Předmět:
Zdroj: LAGOS
ISSN: 1571-0661
DOI: 10.1016/j.entcs.2019.08.064
Popis: A path partition P of a digraph D is a collection of directed paths such that every vertex belongs to precisely one path. Given a positive integer k, the k-norm of a path partition P of D is defined as ∑ P ∈ P min ⁡ { | P i | , k } . A path partition of a minimum k-norm is called k-optimal and its k-norm is denoted by πk(D). A stable set of a digraph D is a subset of pairwise non-adjacent vertices of V(D). Given a positive integer k, we denote by αk(D) the largest set of vertices of D that can be decomposed into k disjoint stable sets of D. In 1981, Linial conjectured that πk(D) ≤ αk(D) for every digraph. We say that a digraph D is arc-spine if V(D) can be partitioned into two sets X and Y where X is traceable and Y contains at most one arc in A(D). In this paper we show the validity of Linial's Conjecture for arc-spine digraphs.
Databáze: OpenAIRE