how to automatically number first column of a table as I type.

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I am fairly new to LibreOffice and I really want to get to grips with it, but I cannot find the instructions I need. I want to have a table in Writer to which I add a new line each day. I would like the first column to number itself automatically when I click the tab button to add the new line.
If I click on the first cell and click on numbering, the number comes up O.K., but then when I click tab again to get to the next cell, and I get another line space and the number moves forward instead of the cursor going to the next cell in the same row.