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:

    In the reproof of chance
    Lies the true proof of men.
    William Shakespeare (1564–1616)

    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)

    It is not enough for theory to describe and analyse, it must itself be an event in the universe it describes. In order to do this theory must partake of and become the acceleration of this logic. It must tear itself from all referents and take pride only in the future. Theory must operate on time at the cost of a deliberate distortion of present reality.
    Jean Baudrillard (b. 1929)