The least number of unknotted arcs lying above the plane in any projection. The knot 05-002 has bridge number 2. Such knots are called 2-bridge
knots. There is a one-to-one correspondence
between 2-bridge knots and rational knots. The knot
08-010 is a 3-bridge knot. A knot with bridge number 
is an 
-embeddable knot where 
.
Bridge Number
See also
Bridge IndexExplore with Wolfram|Alpha
References
Adams, C. C. The Knot Book: An Elementary Introduction to the Mathematical Theory of Knots. New York: W. H. Freeman, pp. 64-67, 1994.Rolfsen, D. Knots and Links. Wilmington, DE: Publish or Perish Press, p. 115, 1976.Referenced on Wolfram|Alpha
Bridge NumberCite this as:
Weisstein, Eric W. "Bridge Number." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/BridgeNumber.html