Autofill a REPEATING series of numbers in Excel

Question

I have been getting on fine with using AutoFill in Excel using the 'fill handle', up to a point...

The problem I have is I can't figure out how to AutoFill a Series of REPEATING numbers (e.g. 1 to 10) in a Column in Excel - such as A1 to A10, then repeating in A11 to A20 and so on?

I tried the 'Fill' option in the Ribbon - Home>Fill>Series (Columns-Linear)-Step Value:1/Stop Value:10 - but that only fills in one 'set' of 1 to 10... how do I get it to repeat either a set number of times, or until a specific Cell, e.g. A100 ?

Answer 1

If you have Microsoft 365 or Office 2021, enter the following formula in A1:

=MOD(SEQUENCE(100)-1,10)+1

It will spill to A1:A100.

In older versions:

Enter 1 in A1.

In A2, enter the formula =MOD(A1, 10)+1

Fill down to A100.

Answer 2

Thanks @HansV -

Having researched both the MOD & SEQUENCE functions in your answer, I have no idea how it works but it does...!

Answer 3

SEQUENCE(100) generates the numbers

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, ..., 100

SEQUENCE(100)-1 returns

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, .., 99.

MOD(..., 10) calculates the remainder of these numbers after dividing them by 10:

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, ..., 9

Finally, we add 1 to this:

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 2, 3, 4, ..., 10

Answer 4

Hi,

Enter this formula in cell A1

=LET(seq,SEQUENCE(10),INDEX(seq,MOD(SEQUENCE(2*COUNTA(seq),,0),10)+1))

Hope this helps.