Cauchy product
= Cauchy product
{c}
{wiki}
The Cauchy product has coefficients $c_n=\sum_{k=0}^na_kb_{n-k}$. Absolute convergence permits regrouping and makes its sum the product of the two sums.
= Cauchy product
{c}
{wiki}
The Cauchy product has coefficients $c_n=\sum_{k=0}^na_kb_{n-k}$. Absolute convergence permits regrouping and makes its sum the product of the two sums.