# How do you find the formula for #a_n# for the arithmetic sequence #4, 3/2, -1, -7/2,...#?

##### 1 Answer

Feb 11, 2017

#### Answer:

If the initial term is

If the initial term is

#### Explanation:

This appears to be an arithmetic sequence (and the question was asked under the heading Arithmetic Sequences)

Checking the difference between successive terms we see that

That is the initial value is reduced by a further

When I learned this stuff (many years ago), the initial term was denoted

It seems that