An $\textit{arithmetic series}$ is the sum of the terms of an arithmetic sequence.For example: $4, 7, 10, 13, \cdots,61$ is a finite arithmetic sequence. $4+7+10+13+ \cdots +61$ is the corresponding arithmetic series. If the first term is $u_{1}$ and the common difference is $d$, the terms are:$$u_{1},u_{1}+d,u_{1}+2d,u_{1}+3d,\cdots$$\( \begin{align} \displaystyle \require{AMSsymbols} \require{color}u_{1} &= u_{1} \\u_{2} &= […]
