Improved Spanning on Theta-5

Prosenjit Bose, Darryl Hill, Aurélien Ooms

We show an upper bound of $\frac{\sin \left(\frac{3\pi }{10}\right)}{\sin \left(\frac{2\pi }{5}\right)-\sin \left(\frac{3\pi }{10}\right)}<5.70$ on the spanning ratio of ${\Theta }_5$-graphs, imp…