Extremal digraphs avoiding distinct walks of length 3 with the same endpoints
Combinatorics
2021-04-20 v1
Abstract
In this paper, we determine the maximum size of digraphs on vertices in which there are no two distinct walks of length with the same initial vertex and the same terminal vertex. The digraphs attaining this maximum size are also characterized. Combining this with previous results, we obtain a full solution to a problem proposed by X. Zhan in 2007.
Cite
@article{arxiv.2104.08498,
title = {Extremal digraphs avoiding distinct walks of length 3 with the same endpoints},
author = {Zejun Huang and Zhenhua Lyu},
journal= {arXiv preprint arXiv:2104.08498},
year = {2021}
}
Comments
11 pages,2 figures