Permutations without repetition using options in categories

Thanks guys! This really helps. Both of your answers do the trick. I am trying to understand what you did and see if I can work with it. I was looking at both your examples how it would work if I want to add parameters of options in the category.
Could you explain to me some things in the formulas?

John:

=INT((ROWS($1:1)-1)/9)+1 What is the information selected? Why 9?

=MOD(INT((ROWS($1:1)-1)/3);3)+1 I understand the first "3" is the position as in 1/3 or 2/3. What is the second 3?

=MOD((ROWS($1:1)-1);3)+1 same question and why the +1?

Davsth:

From your example it is more clear on where the formule gets the information. And I was able to add options and categories, I just can't get the positions right, so I end up with several zero's. Also, I am getting the same option several times, and I need every permutation to be unique.