Help me explore the convergence of red color rounded series. On this photo (the equation below) I used radical indication but it doesn't show me the result. What would be better to use?
$$\color{red}{\sum_{n=1}^{\infty}\frac{1}{n^3\ln(n)}=\text{?}}$$ $$\lim_{n \to \infty}\sqrt[n]{\frac{1}{n^3\ln(n)}} = \lim_{n \to \infty}\frac{\sqrt[n]{1^n}}{\sqrt[n]{3^n} \sqrt[n]{\ln(n)}} = 1$$
Radical Cauchy indication does not help.
Use the comparison with the Riemann series $$\frac1{n^3\ln n}\le \frac1{n^3}\quad\text{for $n$ large enough}$$