The graph isomorphism problem

M Grohe, P Schweitzer - Communications of the ACM, 2020 - dl.acm.org
The graph isomorphism problem Page 1 128 COMMUNICATIONS OF THE ACM |
NOVEMBER 2020 | VOL. 63 | NO. 11 review articles IMA GE B Y NAD A V/SHUTTERS T …

[PDF][PDF] Various properties of various ultrafilters, various graph width parameters, and various connectivity systems

T Fujita - arXiv preprint arXiv, 2024 - researchgate.net
This paper investigates ultrafilters in the context of connectivity systems, defined as pairs (X,
f) where X is a finite set and f is a symmetric submodular function. Ultrafilters, essential in …

A 5-Approximation Algorithm for Treewidth

HL Bodlaender, PG Drange, MS Dregi, FV Fomin… - SIAM Journal on …, 2016 - SIAM
We give an algorithm that for an input n-vertex graph G and integer k>0, in time 2^O(k)n,
either outputs that the treewidth of G is larger than k, or gives a tree decomposition of G of …

Structure theorem and isomorphism test for graphs with excluded topological subgraphs

M Grohe, D Marx - Proceedings of the forty-fourth annual ACM …, 2012 - dl.acm.org
We generalize the structure theorem of Robertson and Seymour for graphs excluding a fixed
graph H as a minor to graphs excluding H as a topological subgraph. We prove that for a …

Faster Isomorphism for 𝑝-Groups of Class 2 and Exponent 𝑝

X Sun - Proceedings of the 55th Annual ACM Symposium on …, 2023 - dl.acm.org
The group isomorphism problem determines whether two groups, given by their Cayley
tables, are isomorphic. For groups with order n, an algorithm with n (log n+ O (1)) running …

Canonisation and definability for graphs of bounded rank width

M Grohe, D Neuen - ACM Transactions on Computational Logic, 2023 - dl.acm.org
We prove that the combinatorial Weisfeiler-Leman algorithm of dimension (3 k+ 4) is a
complete isomorphism test for the class of all graphs of rank width at most k. Rank width is a …

A faster isomorphism test for graphs of small degree

M Grohe, D Neuen, P Schweitzer - SIAM Journal on Computing, 2020 - SIAM
In a recent breakthrough, Babai Proceedings of STOC, ACM, New York, 2016, pp. 684--697
gave a quasipolynomial-time graph isomorphism test. In this work, we give an improved …

Isomorphism testing for graphs of bounded rank width

M Grohe, P Schweitzer - 2015 IEEE 56th Annual Symposium …, 2015 - ieeexplore.ieee.org
We give an algorithm that, for every fixed k, decides isomorphism of graphs of rank width at
most k in polynomial time. As the rank width of a graph is bounded in terms of its clique …

Graph isomorphism parameterized by elimination distance to bounded degree

J Bulian, A Dawar - Algorithmica, 2016 - Springer
A commonly studied means of parameterizing graph problems is the deletion distance from
triviality (Guo et al., Parameterized and exact computation, Springer, Berlin, pp. 162–173 …

An improved isomorphism test for bounded-tree-width graphs

M Grohe, D Neuen, P Schweitzer… - ACM Transactions on …, 2020 - dl.acm.org
We give a new FPT algorithm testing isomorphism of n-vertex graphs of tree-width k in time 2
kpolylog (k) n3, improving the FPT algorithm due to Lokshtanov, Pilipczuk, Pilipczuk, and …