Generate repeating, non repeating permutions and combinations of inputs.

Just tabling a little challenge/discussion piece for us. To generate all repeating, non repeating permutions and combinations of a set of inputs.

Context: we have a list of 4 items in E2. {"P";"Q";"R";"S"}. We can refer to this list (set) as E2#. Above in E1 we have COUNTAed that set to 4. In F1 we have defined 2. In A1:C1 we’ve printed {"Power","Permut","Combin"}.

In A2 we want to define all pairs (re 2) of those 4. Colon seperated. So we’ll end up with 16 outputs.

P:P

P:Q

P:R

P:S

Q:P

…

S:S

In B2, we want all permutations that pair those items. Similar to A but items can’t be repeated within the pairing. They’ll amount to 12:

P:Q

P:R

P:S

Q:P

Q:R

…

S:R

In C2, all combinations. These are unique in their ordering. So having generated P:Q, we can’t generate Q:P. These will number 6.

I’ll screenshot the context into comments, and attempt to edit that into post (help invited). Rewording is also invited if any terminology above is incorrect.

How might we go about this?