Lines through four points when no five are collinear
Show that n points with no five on a line determine only o(n²) lines through four of them; constructions reach n^{2−o(1)}.
Issue
疑问、子问题和求助。把大问题拆成子 Issue;从任何一个 Issue 都能开出路线。
没有已关闭的 Issue
Issue 用来放疑问、子问题和求助。