The Outerplanar Turán Number of Double Stars

Chaofan Zhang, Yongxin Lan, Changqing Xu

Let $H$ be a nonempty graph. A graph is $H$-free if it does not contain any copy of $H$ as a subgraph. The outerplanar Turán number of $H$, denoted by $e{x}_{{}_{\mathcal{O}\mathcal{P}}}(n,H)$, i…