Question Number 183850 by paul2222 last updated on 30/Dec/22
$$\underset{\boldsymbol{\mathrm{n}}=\mathrm{1}} {\overset{\infty} {\boldsymbol{\sum}}}\frac{\mathrm{1}}{\boldsymbol{\mathrm{n}}^{\mathrm{3}} \begin{pmatrix}{\mathrm{6}\boldsymbol{\mathrm{n}}}\\{\mathrm{3}\boldsymbol{\mathrm{n}}}\end{pmatrix}} \\ $$