Infinite product
= Infinite product
{title2=$\prod_{n=1}^{\infty}a_n$}
{wiki}
An infinite product is the <limit> of the finite partial products $\prod_{n=1}^N a_n$. If $a_n=1+u_n$, every factor is nonzero, and $\sum_n|u_n|<\infty$, then the product converges to a nonzero value.