Problems involving harmonic numbers are so strange in solution way and those approaches or results are attracting the attention of students interested in mathematics as well as mathematicians and engineers, as there are many areas of application. In scientific and technological calculations that occur in various fields of mathematics and engineering, computational problems associated with various mathematical constants are often encountered, some of which are important tools for solving scientific and technological problems. There have been many open problems that have not been addressed before, due to the high level of scientific theory and the high performance of computer-based computing tools. Nevertheless, the world of mathematics still has a lot of problems to be discovered, so new and diverse methods are needed to solve these problems. This book contains open problems and challenging problems presented in several mathematical reference books and add their new generalizations written by us.
