What is the problem specifically. Are you trying to guess the next term. Do you want the general term? The sum of them?
Start with the arithmetic sequences first.
Please take a look at these.
http://www.mathsisfun.com/algebra/seque … metic.html
http://www.mathsisfun.com/algebra/seque … -rule.html
http://www.mathsisfun.com/algebra/sequences-series.html
Now you are ready to ask a good question!
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