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arXiv · 2610.06788

Large corank of dense random regular digraphs

Huaijin Liang·Kexin Yu·Tingzhou Yu
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Abstract

Let $1\le k\le n$ and let $A$ be the adjacency matrix of a uniformly random $d$-regular directed graph on $n$ vertices. Suppose that $λn\le d \le (1-λ)n$ for a fixed $0<λ\le 1/2$. We show that there exists $c_λ>0$ depending only on $λ$ such that $$ \mathbb{P}[\operatorname{rank}(A)\le n-k]\le 2e^{-c_λ kn}. $$ This gives a large corank extension of the exponential singularity bound of Jain, Sah, and Sawhney.

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Huaijin Liang, Kexin Yu, Tingzhou Yu. 2026-10-05. Large corank of dense random regular digraphs. https://arxiv.org/abs/2610.06788

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