Euler's criterion


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Euler's criterion

[′ȯi·lərz krī′tir·ē·ən]
(mathematics)
A criterion for the congruence x n a (mod m) to have a solution, namely that a φ/d≡1 (mod m), where φ = φ(m) is Euler's phi function evaluated at m, and d is the greatest common divisor of φ and n.
References in periodicals archive ?
For any integer a with (a, p) = 1, from the Euler's criterion (See Theorem 9.