When there are infinite poles, the series is equal to the sum of fractional times. The sum of series refers to a series in which the ratio of each term to its previous term is equal to the same constant from the second term, usually expressed by G and P. This constant is called the common ratio of geometric series, usually expressed by the letter Q (q≠0), and the geometric series is a 1≠0. Where each item in {an} is not 0. Sum of power series, when the numerator is less than or equal to the denominator, we need to discuss 0 and power series, which is one of the important concepts in mathematical analysis. Every item in the exponential column is the power of (x-a) corresponding to the serial number n of the series item (n is an integer counting from 0, and a is a constant). Power series is an important concept in mathematical analysis, which has been used as a basic content in many fields such as real variable function and complex variable function.