I'm reading Manin's article on formal groups and I have a problem with lemmaLemma 1.1. consider kConsider $k$ a prefect ring of characteristic p$p$ and (A,m,k)$(A,m,k)$ a noetherian complete local ring of the same characteristic such that $X=spf\, A$$X=\operatorname{spf} A$ is a formal group. Manin wants to prove $X$ is a direct limit of finite group schemes over $k$.
defineDefine $m^{(p^n)}$ as the ideal generated by $$\{x^{p^n}|x\in m\}$$$$\{x^{p^n}|x\in m\}.$$ (Manin useuses the notation $m^{p^n}$ but I don't understand why $m^{p^n}$ is generated by these elements.) heHe proves that $\frac{A}{m^{(p^n)}}$ are Hopf algebras and because $A$ is complete we have $A=\varprojlim \frac{A}{m^{(p^n)}}$ as rings.
I don't understand if $m^{(p^n)}$ is really equal to $m^{p^n}$ and, if not, why A$A$ and $\varprojlim \frac{A}{m^{(p^n)}}$ are equalcan be identified as topological rings?