Planar Turán number of the 7-cycle

Ruilin Shi, Zach Walsh, Xingxing Yu

The $\text{planar Turaˊn number}$ ${\text{ex}}_{\mathcal{P}}(n,H)$ of a graph $H$ is the maximum number of edges in an $n$-vertex planar graph without $H$ as a subgraph. Let $C_{\e…