G
o
o
g
l
e
×
Please click
here
if you are not redirected within a few seconds.
All
Images
Videos
News
Maps
Shopping
Books
Search tools
Any time
Any time
Past hour
Past 24 hours
Past week
Past month
Past year
All results
All results
Verbatim
Crossing number
Graph theory
View all
In graph theory, the crossing number cr of a graph G is the lowest number of edge crossings of a plane drawing of the graph G. For instance, a graph is planar if and only if its crossing number is zero.
Wikipedia