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arXiv · 2202.06810

Structured Codes of Graphs

Noga Alon·Anna Gujgiczer·János Körner·Aleksa Milojević·Gábor Simonyi
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Abstract

We investigate the maximum size of graph families on a common vertex set of cardinality $n$ such that the symmetric difference of the edge sets of any two members of the family satisfies some prescribed condition. We solve the problem completely for infinitely many values of $n$ when the prescribed condition is connectivity or $2$-connectivity, Hamiltonicity or the containment of a spanning star. We also investigate local conditions that can be certified by looking at only a subset of the vertex set. In these cases a capacity-type asymptotic invariant is defined and when the condition is to contain a certain subgraph this invariant is shown to be a simple function of the chromatic number of this required subgraph. This is proven using classical results from extremal graph theory. Several variants are considered and the paper ends with a collection of open problems.

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Noga Alon, Anna Gujgiczer, János Körner, Aleksa Milojević, Gábor Simonyi. 2022-02-14. Structured Codes of Graphs. https://arxiv.org/abs/2202.06810

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