Hi, I have an index array that works properly in a single cell. How can I copy this down the column so that it calls upon the next row in the table? See example below:

Formula Entered in column C =(INDEX(A:A,(2)))&(INDEX(B:B,(2)))

1 A B C
2 http://help.org/ 2201 http://help.org/2201 (This is correct, and the return I was wanting)
3 http://help.org/ 1250 (I want to copy the above formula here, but call upon row 3 instead of 2. Is there a way without manually changing the 2 in the formula to 3?)
4 http://help.org/ 8952
5 http://help.org/ 3452

If there is a better formula than the one I used that will accomplish the same result, please let me know. I will be using this for over 8,000 rows! I am not very knowledgeable with excel, excel language or lingo, so please respond as if I understand noting about excel.

Thanks in advance!