Explicit factorization of $x^n-1\in \mathbb F_q[x]$
  Let $\mathbb F_q$ be a finite field and $n$ a positive integer. In this article, we prove that, under some conditions on $q$ and $n$, the polynomial $x^n-1$ can be split into irreducible binomials $x^t-a$ and an explicit factorization into irreducible factors is given.   Finally, weakening one of our hypothesis, we also obtain factors of the form $x^{2t}-ax^t+b$ and explicit splitting of $x^n-1$ into irreducible factors is given. 
F.E. Brochero Mart\'inez, C. R. Giraldo Vergara, L. Batista de   Oliveira
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