One way is to type 17 in the first cell, 34 in the second cell, then select
the 2 cells and fill down as appropriate.
Another way is to put =17*ROWS($1:1) in the first cell and fill down.

Enter 17 in A1 and 34 in A2.

Select both A1 and A2 then drag down as needed.

if you anchor your 17 (or any other number) near the top of a column,
say B5 and in the row cell below in the same column enter =B5, you can
then simply drag down column B as far as you wish to go.

I have several bank account statements set similarly.

-Please reply to group as my email addr is fake!

-Regards CC

Enter 17 in A1

In A2 enter  =$C$1 + C1

Copy down.

Gord Dibben  MS Excel MVP