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Figure-eight knot | |
---|---|

Common name | Figure-eight knot |

Arf invariant | 1 |

Braid length | 4 |

Braid no. | 3 |

Bridge no. | 2 |

Crosscap no. | 2 |

Crossing no. | 4 |

Genus | 1 |

Hyperbolic volume | 2.02988 |

Stick no. | 7 |

Unknotting no. | 1 |

Conway notation | [22] |

A–B notation | 4_{1} |

Dowker notation | 4, 6, 8, 2 |

Last / Next | 3_{1} / 5_{1} |

Other | |

alternating, hyperbolic, fibered, prime, fully amphichiral, twist |

In knot theory, a **figure-eight knot** (also called **Listing's knot**^{[1]}) is the unique knot with a crossing number of four. This makes it the knot with the third-smallest possible crossing number, after the unknot and the
trefoil knot. The figure-eight knot is a prime knot.

**^**"Listing knot - Encyclopedia of Mathematics".*encyclopediaofmath.org*. Retrieved 2020-06-25.