We present here a large collection of harmonic and quadratic harmonic sums, that can be useful in applied questions, e.g., probabilistic ones. We find closed-form formulae, that we were not able to locate in the literature.

翻译：本文给出了大量在概率等应用问题中有用的调和级数与二次调和级数。我们找到了文献中未能定位的闭式公式。