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arXiv · 0706.1103

On the threshold for k-regular subgraphs of random graphs

Pawel Pralat·Jacques Verstraete·Nicholas Wormald
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Abstract

The $k$-core of a graph is the largest subgraph of minimum degree at least $k$. We show that for $k$ sufficiently large, the $(k + 2)$-core of a random graph $\G(n,p)$ asymptotically almost surely has a spanning $k$-regular subgraph. Thus the threshold for the appearance of a $k$-regular subgraph of a random graph is at most the threshold for the $(k+2)$-core. In particular, this pins down the point of appearance of a $k$-regular subgraph in $\G(n,p)$ to a window for $p$ of width roughly $2/n$ for large $n$ and moderately large $k$.

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Pawel Pralat, Jacques Verstraete, Nicholas Wormald. 2007-06-08. On the threshold for k-regular subgraphs of random graphs. https://arxiv.org/abs/0706.1103

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