In A1:A100 I have numbers (I used 1,2,3... so I could easily check my
result)
In D1

10 I have the sequence 1, 11,21... (Just type 1, 11; select both;
pull the fill handle down)
In E1 I have the formula =INDIRECT("A"&$D1+COLUMN()-5)
This evaluates to =INDIRECT("A1") in that cell; The 5 is these because I
started in column E
Copied this across and down to fill E1:M10
Now I have
1,2,3..10
11,12,13..20
etc
Now I can use Copy followed by Paste Special - Values to convert to real
numbers if I so wish
best wishes