This book is the mathematical reference book which is helpful and accessible for not only professional mathematicians but also readers who have a little knowledge of mathematics. Special functions and mathematical constants are pervasive in all fields of science and industry. The gamma function can be thought of as an extension of the factorial function, which is defined only for positive integers. The most remarkable point of the book is the method to construct continued fraction approximation and its applications. The book consists of 3 chapters. In Chapter 1, we give the introduction for...