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摘要： Let a power series $$S(x)=\sum_{n=1}^{\infty}\frac{x^{n}}{4n+1},$$ then $1$ is the radius of convergence of $S$ .In fact $S(x)$ convergens for each $x... 阅读全文

摘要： Let $\sum_{n=1}^{\infty}a_{n}$ and $\sum_{n=1}^{\infty}b_{n}$ ,both of them are convergent series with positive terms .For every $\mu+\nu\geq1,\mu>0,\... 阅读全文