A sequence can be thought of as a list of numbers written in a definite order:

a_{1}, a_{2}, a_{3}, ..., a_{n}, ...

The number a_{1} is called the first term, a_{2} is the second term, and in general a_{n} is the nth term.

The terms of a sequence often follow a particular pattern. In those instances, we can determine the general term that expresses every term of the sequence. For example:

Sequence

General Term

3, 6, 9, 12,...
1,3,5,7,...
2,4,8,16,...

3n
2n-1
2^{n}

Given a_{n}=3n+2, find a_{1}, a_{2}, a_{3} and a_{4}.

By substituting n=1,2,3,4 in the general term of the sequence, we obtain: