Three-twist knot

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Three-twist knot
Blue Three-Twist Knot.png
Common name[[Figure-of-nine knot[1]]]
Arf invariant0
Braid length6
Braid no.3
Bridge no.2
Crosscap no.2
Crossing no.5
Hyperbolic volume2.82812
Stick no.8
Unknotting no.1
Conway notation[32]
A-B notation52
Dowker notation4, 8, 10, 2, 6
Last /Next5161
alternating, hyperbolic, prime, reversible, twist

In knot theory, the three-twist knot is the twist knot with three-half twists. It is listed as the 52 knot in the Alexander-Briggs notation, and is one of two knots with crossing number five, the other being the cinquefoil knot.

The three-twist knot is a prime knot, and it is invertible but not amphichiral. Its Alexander polynomial is

its Conway polynomial is

and its Jones polynomial is


Because the Alexander polynomial is not monic, the three-twist knot is not fibered.

The three-twist knot is a hyperbolic knot, with its complement having a volume of approximately 2.82812.

If the fibre of the knot in the initial image of this page were cut at the bottom right of the image, and the ends were pulled apart, it would result in a single-stranded figure-of-nine knot (not the figure-of-nine loop).


Assembling of Three-twist knot.


  1. ^ Pinsky, Tali (1 September 2017). "On the topology of the Lorenz system". Proc. R. Soc. A. The Royal Society. p. 20170374. doi:10.1098/rspa.2017.0374. Retrieved 26 August 2018. (b) the knot with three half-twists, called the 52 knot.
  2. ^ "5_2", The Knot Atlas.