Relations between convergence on boundary of power series, and the uniformity of convergence

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Given a power series $\sum_{n=0}^\infty a_n x^n \ ,x \in \mathbb R\ $ with radius of convergence $R$.

Is that true that:

  • If the series does not converge at one boundary, $R$ or $-R$, then the convergence on $(R,-R)$ is not uniform.

  • If the series converge at $R$ (or $-R$), then the convergence is uniform on $[0,R]$ (or $[-R,0]$). (not just from $0$, from any $r<R$.)