Crossing Number

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, my first [bicycle] had an intrinsic beauty. And it opened for me an era of all but flying, which roads emptily crossing the airy, gold-gorsy Common enhanced. Nothing since has equalled that birdlike freedom.”
    —Elizabeth Bowen (1899–1973)

    “The Oregon [matter] and the annexation of Texas are now all- important to the security and future peace and prosperity of our union, and I hope there are a sufficient number of pure American democrats to carry into effect the annexation of Texas and [extension of] our laws over Oregon. No temporizing policy or all is lost.”
    —Andrew Jackson (1767–1845)