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تسجيل مستخدم جديدConservation of the noetherianity by perfect transcendental field extensions
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Let $k$ be a perfect field of characteristic $p>0$, $k(t)_{per}$ the perfect closure of $k(t)$ and $A$ a $k$-algebra. We characterize whether the ring $Aotimes_k k(t)_{per}$ is noetherian or not. As a consequence, we prove that the ring $Aotimes_k k(t)_{per}$ is noetherian when $A$ is the ring of formal power series in $n$ indeterminates over $k$.
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