crossing lemmaCrossingLemma2002-12-28 19:38:412004-01-24 23:25:32Theorem\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{amsfonts}
\DeclareMathOperator{\crn}{cr}The crossing number of a \PMlinkname{graph}{Graph} $G$ with $n$ \PMlinkname{vertices}{Graph} and $m\geq 4n$ \PMlinkname{edges}{Graph} is
\begin{equation*}
\crn(G)\geq \frac{1}{64}\frac{m^3}{n^2}.
\end{equation*}