##  [Carmichael Number](/carmichael-number) 

  ##  [Carmichael Number](https://puremath.quantumdictionary.io/carmichael-number-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A composite integer n such that for every integer a coprime to n, a^{n−1} ≡ 1 (mod n); therefore n behaves like a prime in the Fermat congruence for all bases coprime to it.