2 papers
cs.LO2026
Going deep and going wide: Counting logic and homomorphism indistinguishability over graphs of bounded treedepth and treewidth
Isolde Adler, Eva Fluck, Tim Seppelt +1
We study the expressive power of first-order logic with counting quantifiers, especially the -variable and quantifier-rank- fragment, using homomorphism indistinguishability.…
math.CO2026
A structural duality for path-decompositions into parts of small radius
Sandra Albrechtsen, Reinhard Diestel, Ann-Kathrin Elm +4
It is an easy observation that if a graph~ admits a path-decomposition whose parts have small radius, then contains no large subdivision of or as a (quasi-)g…