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A. Cohn's irreducibility criterion

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Assume $n  \geq 2$ is an integer  and that $P$ is a polynomial with coefficients in $\{0,1,\ldots,n-1\}$. If $P(n)$ is prime then $P(x)$ is \PMlinkname{irreducible}{IrreduciblePolynomial2} in $\mathbb{Z}[x]$.
A proof is given in \cite{MRM}.

 A. Cohn \cite{PZ} proved this theorem for the case $n=10$.

This special case of the above theorem is sketched as problem 128, Part VIII, in \cite{PZ}.

George Pólya, Gabor Szego,
 {\it Problems and Theorems in Analysis II},
 Classics in Mathematics 1998.
M. Ram Murty, {\it Prime Numbers and Irreducible Polynomials}, American
Mathematical Monthly, vol. 109, (2002), 452-458.