Crossing number may refer to:
- Crossing number (knot theory) of a knot is the minimal number of crossings in any knot diagram for the knot.
- The average crossing number is a variant of crossing number obtained from a three-dimensional embedding of a knot by averaging over all two-dimensional projections.
- Crossing number (graph theory) of a graph is the minimal number of edge intersections in any planar representation of the graph.
Famous quotes containing the words crossing and/or number:
“Twenty men crossing a bridge,
Into a village,
Are twenty men crossing twenty bridges,
Into twenty villages,
Or one man
Crossing a single bridge into a village.”
—Wallace Stevens (1879–1955)
“[The] elderly and timid single gentleman in Paris ... never drove down the Champs Elysees without expecting an accident, and commonly witnessing one; or found himself in the neighborhood of an official without calculating the chances of a bomb. So long as the rates of progress held good, these bombs would double in force and number every ten years.”
—Henry Brooks Adams (1838–1918)