Eisenstein sum

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In mathematics, an Eisenstein sum is a finite sum depending on a finite field and related to a Gauss sum. Eisenstein sums were introduced by Eisenstein in 1848, [1] named "Eisenstein sums" by Stickelberger in 1890, [2] and rediscovered by Yamamoto in 1985, [3] who called them relative Gauss sums.

Contents

Definition

The Eisenstein sum is given by

where F is a finite extension of the finite field K, and χ is a character of the multiplicative group of F, and α is an element of K. [4]

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