1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30

If I type 1 into a cell, I can click on the bottom-right of that cell and drag the plus sign to the right until I've selected numerous cells, and it autofills in sequential order... but only one row at a time.

At the moment, I would have to manually type 11, and then fill the next row. Then again, manually type 20 and drag fill another row, etc.

I try dragging over multiple rows, but Excel won't let me. I can drag horizontal or vertical, but only ever one row or column at a time.

Is there a faster way to autofill to get the result seen at the top?