How to autofill a series of numbers of this type in Excel: "1."?

Question

excel

How to autofill a series of numbers of this type in Excel: "1."? There should be a similar sequence:
1.
2.
3.
...
Each digit is a separate cell.
Excel stubbornly refuses to extend the row as it should.

Answer 1

Ilya Borisenko , It is
more logical to make a series of numbers without a dot, and add the dot in the cell format by writing a string in the custom format
Then the number will be stored in the cell, and the number with a dot will be displayed.

Answer 2

=ROW()&"."