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Revision difference : nil and nilpotent ideals
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An element $x$ of a ring is \emph{nilpotent} if $x^n = 0$ for some positive integer $n$. An element $x$ of a ring is \emph{nilpotent} if $x^n = 0$ for some positive integer $n$.
A ring $R$ is \emph{nil} if every element in $R$ is nilpotent. Similarly, a one- or two-sided ideal is called \emph{nil} if each of its elements is nilpotent. A ring $R$ is \emph{nil} if every element in $R$ is nilpotent. Similarly, a one- or two-sided ideal is called \emph{nil} if each of its elements is nilpotent.
A ring $R$ [resp. a one- or two sided ideal $S$] is \emph{nilpotent} if $R^n = 0$ [resp. $A^n = 0$] for some positive integer $n$.
A ring $R$ [resp. a one- or two sided ideal $A$] is \emph{nilpotent} if $R^n = 0$ [resp. $A^n = 0$] for some positive integer $n$.
A ring or an ideal is \emph{locally nilpotent} if every finitely generated subring is nilpotent. A ring or an ideal is \emph{locally nilpotent} if every finitely generated subring is nilpotent.
The following implications hold for rings (or ideals): The following implications hold for rings (or ideals):
$$\text{nilpotent} \quad\Rightarrow \text{locally nilpotent} \quad\Rightarrow \text{nil}$$ $$\text{nilpotent} \quad\Rightarrow \text{locally nilpotent} \quad\Rightarrow \text{nil}$$