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arXiv · 2603.03601

Logical aspects of isomorphism of controllable graphs and cospectrality of distance-regularized graphs

Aida Abiad·Anuj Dawar·Octavio B. Zapata-Fonseca
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Abstract

We consider isomorphism of controllable graphs and cospectrality of distance-regularized graphs (which are known to be distance-regular or distance-biregular) in relation to logical definability. While most characterizations of these equivalence relations for such graph classes are of algebraic and spectral flavor, here we inject tools from first-order logic, extending and unifying several existing results.

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Aida Abiad, Anuj Dawar, Octavio B. Zapata-Fonseca. 2026-03-04. Logical aspects of isomorphism of controllable graphs and cospectrality of distance-regularized graphs. https://arxiv.org/abs/2603.03601

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