Distance labelings: a generalization of Langford sequences

A Langford sequence of order m and defect d can be identified with a labeling of the vertices of a path of order 2m in which each labeled from d up to d + m - 1 appears twice and in which the vertices that have been label with k are at distance k. In this paper, we introduce two generalizations of this labeling that are related to distances. Articles in this journal are published under Creative Commons Attribution 3.0 License http://creativecommons.org/licenses/by/3.0/