English

Constructing Hard Examples for Graph Isomorphism

Computational Complexity 2019-03-19 v2 Discrete Mathematics

Abstract

We describe a method for generating graphs that provide difficult examples for practical Graph Isomorphism testers. We first give the theoretical construction, showing that we can have a family of graphs without any non-trivial automorphisms which also have high Weisfeiler-Leman dimension. The construction is based on properties of random 3XOR-formulas. We describe how to convert such a formula into a graph which has the desired properties with high probability. We validate the method by an experimental implementation. We construct random formulas and validate them with a SAT solver to filter through suitable ones, and then convert them into graphs. Experimental results demonstrate that the resulting graphs do provide hard examples that match the hardest known benchmarks for graph isomorphism.

Keywords

Cite

@article{arxiv.1809.08154,
  title  = {Constructing Hard Examples for Graph Isomorphism},
  author = {Anuj Dawar and Kashif Khan},
  journal= {arXiv preprint arXiv:1809.08154},
  year   = {2019}
}

Comments

20 pages. A revised version incorporating new experimental results

R2 v1 2026-06-23T04:14:09.086Z