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arXiv · 2608.13025

A counterexample to the Foregger-Sinkhorn tie-point conjecture

Yair Lavi
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Abstract

The Foregger-Sinkhorn tie-point conjecture asserts that if a nearly decomposable doubly stochastic matrix minimizes the permanent on a face and the permanental cofactor at a prescribed zero is larger than its permanent, then that zero is a tie point. We give a counterexample in dimension eight.

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Yair Lavi. 2026-08-13. A counterexample to the Foregger-Sinkhorn tie-point conjecture. https://arxiv.org/abs/2608.13025

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