Smallest Cunningham chains of a given length. Numbers in red indicate smallest known, as opposed to smallest, and numbers in bold are those I have found personally.

See Dirk Augustin's Cunningham chain page for more Cunningham chain records — previously known chains taken from there.

Length | Type | First prime in chain | Digits | Found by |
---|---|---|---|---|

19 | 1^{st} |
|||

2^{nd} |
42008163485623434922152331 | 26 | Chermoni and Wroblewski, March 2014 | |

18 | 1^{st} |
776208125345634679522109 |
24 | Armitage, January 2021 |

2^{nd} |
773377687199227745520601 |
24 | Armitage, January 2021 | |

17 | 1^{st} |
2759832934171386593519 | 22 | Wroblewski, May 2008* |

2^{nd} |
8058978143544782179441 |
22 | Armitage, January 2021 |

* Proved smallest by Sorenson and Webster, Two algorithms to find primes in patterns, Section 4.3 (arXiv).