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arXiv · 1610.01276

On the Cycle Space of a Random Graph

Jacob D. Baron·Jeff Kahn
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Abstract

Write $\mathcal{C}(G)$ for the cycle space of a graph $G$, $\mathcal{C}_κ(G)$ for the subspace of $\mathcal{C}(G)$ spanned by the copies of the $κ$-cycle $C_κ$ in $G$, $\mathcal{T}_κ$ for the class of graphs satisfying $\mathcal{C}_κ(G)=\mathcal{C}(G)$, and $\mathcal{Q}_κ$ for the class of graphs each of whose edges lies in a $C_κ$. We prove that for every odd $κ\geq 3$ and $G=G_{n,p}$, \[\max_p \, \Pr(G \in \mathcal{Q}_κ\setminus \mathcal{T}_κ) \rightarrow 0;\] so the $C_κ$'s of a random graph span its cycle space as soon as they cover its edges. For $κ=3$ this was shown by DeMarco, Hamm and Kahn (2013).

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Jacob D. Baron, Jeff Kahn. 2016-10-05. On the Cycle Space of a Random Graph. https://doi.org/10.1002/rsa.20785

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