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arXiv · 2608.15302

Odd minors or odd immersions in graphs with independence number two

Antonia Bermúdez·Bruno L. Netto·Daniel A. Quiroz
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Abstract

Kühn, Sauermann, Steiner and Wigderson recently disproved the Odd Hadwiger Conjecture, even for graphs with independence number 2. For this class of graphs the conjecture is known to be equivalent to the following: every $n$-vertex graph $G$ with independence number 2 contains $K_{\lceil \frac n2 \rceil}$ as an odd minor. While this does not hold, we prove that every graph $G$ with independence number 2 contains $K_{\lceil \frac n2 \rceil}$ as an odd minor or as a totally odd immersion.

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Antonia Bermúdez, Bruno L. Netto, Daniel A. Quiroz. 2026-08-15. Odd minors or odd immersions in graphs with independence number two. https://arxiv.org/abs/2608.15302

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