"rayybay" wrote:
Could that formula be modifed so after 26 characters, it started with A1,
B1... instead of AA, AB...?

Try this in any starting cell, say in B2:
=IF(ROWS($1:1)26,CHAR(MOD(ROWS($1:1)-1,26)+65)&INT((ROWS($1:1)-1)/26),CHAR(MOD(ROWS($1:1)-1,26)+65))
Copy down as far as required.

The expression will return the series:
A,B, ... Z,A1,B1, ... Z1,A2,B2, ... Z2,A3,B3 ... and so on, all the way
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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