I have two worksheets in the same spreadsheet file.
In one, when I type 1,2,3,... in a column I am able to auto fill (using the auto fill drag handle) the following cells in the column as a "Series" and have it create cells following with 4,5,6, etc.
In the other, typing 1,2,3,... in a column and selecting the auto fill drag handle just copies the pattern. Selecting the auto fill menu option shows me that the "Series" item is greyed out. Why? How can I "ungrey" it and activate the auto-fill-as-a-numerical-series-option in this second spreadsheet?