# Category: Series and Sequences

## Sequences

In simple words sequence is a list of numbers written in definite order: ${a}_{{1}},{a}_{{2}},\ldots,{a}_{{n}}$. ${a}_{{1}}$ is first term, ${a}_{{2}}$ is second term, and, in general, ${a}_{{n}}$ is n-th term. We deal with infinite sequences, so each term ${a}_{{n}}$ will have a successor ${a}_{{{n}+{1}}}$.