Proofs of Fermat's Little Theorem - Proof Using Group Theory

Proof Using Group Theory

This proof requires the most basic elements of group theory.

The idea is to recognise that the set G = {1, 2, …, p − 1}, with the operation of multiplication (taken modulo p), forms a group. The only group axiom that requires some effort to verify is that each element of G is invertible. Taking this on faith for the moment, let us assume that a is in the range 1 ≤ ap − 1, that is, a is an element of G. Let k be the order of a, so that k is the smallest positive integer such that

By Lagrange's theorem, k divides the order of G, which is p − 1, so p − 1 = km for some positive integer m. Then

Read more about this topic:  Proofs Of Fermat's Little Theorem

Famous quotes containing the words proof, group and/or theory:

    The thing with Catholicism, the same as all religions, is that it teaches what should be, which seems rather incorrect. This is “what should be.” Now, if you’re taught to live up to a “what should be” that never existed—only an occult superstition, no proof of this “should be”Mthen you can sit on a jury and indict easily, you can cast the first stone, you can burn Adolf Eichmann, like that!
    Lenny Bruce (1925–1966)

    For me, as a beginning novelist, all other living writers form a control group for whom the world is a placebo.
    Nicholson Baker (b. 1957)

    The theory of truth is a series of truisms.
    —J.L. (John Langshaw)