English

Semi-transitivity of directed split graphs generated by morphisms

Combinatorics 2021-08-13 v1

Abstract

A directed graph is semi-transitive if and only if it is acyclic and for any directed path u1u2utu_1\rightarrow u_2\rightarrow \cdots \rightarrow u_t, t2t \geq 2, either there is no edge from u1u_1 to utu_t or all edges uiuju_i\rightarrow u_j exist for 1i<jt1 \leq i < j \leq t. In this paper, we study semi-transitivity of families of directed split graphs obtained by iterations of morphisms applied to the adjacency matrices and giving in the limit infinite directed split graphs. A split graph is a graph in which the vertices can be partitioned into a clique and an independent set. We fully classify semi-transitive infinite directed split graphs when a morphism in question can involve any n×mn\times m matrices over {1,0,1}\{-1,0,1\} with a single natural condition.

Keywords

Cite

@article{arxiv.2108.05483,
  title  = {Semi-transitivity of directed split graphs generated by morphisms},
  author = {Kittitat Iamthong and Sergey Kitaev},
  journal= {arXiv preprint arXiv:2108.05483},
  year   = {2021}
}

Comments

28 pages, 1 figure

R2 v1 2026-06-24T05:02:55.381Z