high

Can't believe how I enter numbers one by one in the past.
Always google your problems before doing anything stupid.

Here is the link to the function, which is dead easy!

http://office.microsoft.com/en-us/excel/HP011542321033.aspx

Simply enter a few numbers in a row or column with the kind of pattern you need, e.g. 1, 2, 3 or 2, 4, 6

Then drag down or across to cover the range of numbers you need

go to Edit --> Fill --> Series --> (choose column/row first) Autofill

Done!