Abstract

Given a graph G, a function f: V(G) -> {1, 2, ..., k} is a k-ranking of G if f(u) = f(v) implies every u - v path contains a vertex w such that f(w) > f(u). A k-ranking is minimal if the reduction of any label greater than 1 violates the described ranking property. The a-rank number of G, denoted u,(G) equals the largest k such that G has a minimal k-ranking. We establish new results involving minimal rankings of paths and in particular we determine u(Pn), a problem suggested by Laskar and Pillone in 2000. We show u(Pn) = [log2 (n + 1)] + [log2(n + 1 - (2^([log2n]-1))] (Refer to PDF file for exact formulas).

Publication Date

8-17-2003

Comments

Presentation at the 34th Southeastern International Conference on Combinatorics, Graph Theory, and Computing, Florida Atlantic University, Boca Raton, FL, March 2003. Research partially supported by JetBlue Airways, Kay & Tony Carlisi, and Timothy Gilbert. Partially supported by a 2002 RIT COS Dean’s Summer Research Fellowship Grant Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type

Article

Department, Program, or Center

School of Mathematical Sciences (COS)

Campus

RIT – Main Campus

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