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:
“This is the Night Mail crossing the Border,
Bringing the cheque and the postal order,
Letters for the rich, letters for the poor,
The shop at the corner, the girl next door.”
—W.H. (Wystan Hugh)
“My idea is that the world outside—the so-called modern world—can only pervert and degrade the conceptions of the primitive instinct of art and feeling, and that our only chance is to accept the limited number of survivors—the one- in-a-thousand of born artists and poets—and to intensify the energy of feeling within that radiant centre.”
—Henry Brooks Adams (1838–1918)