Combinations Problem

I want to generate a list of possible combinations of pairs of (subsets of six) letters and numbers.

For example:

1 2 3
A
B
C
D
E
F

The first set of six pairs would be:
Set 1 = A1,B1,C1,D1,E1,F1
Set 2 = A1,B1,C1,D1,E1,F2
Set 3 = A1,B1,C1,D1,E1,F3
Set 4 = A1,B1,C1,D1,E2,F1
Set 5 = A1,B1,C1,D1,E3,F1
Set 6 = A1,B1,C1,D1,E2,F2


Can anyone help with VBA algorithm to generate the combinations described above?

Wouldn't the first six be: ??

Set 1 = A1,B1,C1,D1,E1,F1
Set 2 = A1,B1,C1,D1,E1,F2
Set 3 = A1,B1,C1,D1,E1,F3
Set 4 = A1,B1,C1,D1,E2,F1
Set 5 = A1,B1,C1,D1,E2,F2
Set 6 = A1,B1,C1,D1,E2,F3

would "A1,B1,C1,D1,E1,F1" be different from "F1,B1,C1,D1,E1,A1"? If not, then the letters don't mater, since they're static. What your list then becomes is basically:
111111
111112
111113
111121
111122
111123
...

Are you allowing more then just the first 6 letters? If so, then that changes things too.

Thanks for your quick response. You're right. The first six are indeed as you outlined them. Also, the set "A1,B1,C1,D1,E1,F1" is the same as "F1,B1,C1,D1,E1,A1". For practical purposes, the final output would not allow all letters to take on the same number values as in "A1,B1,C1,D1,E1,F1" or its mirror. "A2,B2,C2,D2,E2,F2" and "A3,B3,C3,D3,E3,F3" are not allowed either.

The letters are limited to the first six letters of the alphabet.