Commonly, the terms of a series come from a ring, often the field of the real numbers or the field of the complex numbers. If so, the set of all series is also itself a ring, one in which the addition consists of adding series terms together term by term and the multiplication is the Cauchy product.
Commonly the terms of a series come from a ring, often the field of the real numbers or the field of the complex numbers. If so, the set of all series is also itself a ring, one in which the addition consists of adding series terms together term by term and the multiplication is the Cauchy product