A String of Pearls: Proofs of Fermat's Little Theorem

Hing Lun Chan, Michael Norrish


We discuss mechanised proofs of Fermat's Little Theorem in a variety of styles, focusing in particular on an elegant combinatorial ``necklace'' proof that has not been mechanised previously.
What is elegant in prose turns out to be long-winded mechanically, and so we examine the effect of explicitly appealing to group theory. This has pleasant consequences both for the necklace proof, and also for some of the direct number-theoretic approaches.


number theory; automated reasoning

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DOI: 10.6092/issn.1972-5787/3728

Copyright (c) 2013 Hing Lun Chan, Michael Norrish

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