Offset/Array a set of groups (unique, not copies)?

[prevision]

I use a program that generates many groups that are more or less on top of one another. As I need to work with each one separately, it would be great it I could simply select all the groups, chose a direction (red axis, etc.) give a distance value and have each outline be be spaced out from one another as follows:

group 1 stays in place
group 2 is moved distance x along axis
group 3 is moved distance 2x along axis
group 4 is moved distance 3x along axis. . . and on, you get the idea.

The order of which group goes first, 2nd, etc. would be the same as they appear in the outliner.

Conceptually, this is sort of inbetween an unfold and an array. Does such a tool exist?