Excel column autofill (autoincrement with formula)

Question

500 employees will have 3 hours of work each day (for sample made weekday image sample). so i tried with auto increment for B2 cell "=sum(A2+3)". problem arise when i try to enter Absent data or the cell is cleared the data starts from 3 like in E4 or like in E5. need to Enter AA for absent data for that day.

Answer 1

So base the calculation on col A only and multiply the 3 by the column number less 1:

=$A2+(3*(col()-1))

as the column position will multiply by 1, 2 or 3 etc similar to the progression you expected from your method.