Hi Ed, like Pilou mentions there's already a specific array tool for making linear arrays...

It has some UI controls for various modes, you give it the number of elements to make in the array and you can then either pick an offset between each item (the default mode labeled Mode: "Offset, Count"), which I think is the same as the *x mode you're asking for, or you can switch it to Mode: Extent, Count where the points you use are the full extent instead of an offset, I think the same as the /x mode you're asking about. Then there's also a 3rd mode called "Offset, Extent", where you give it 2 distances and it figure out the number of items to make instead of giving it the number of items.

Check out here for a demo of the different modes:
http://moi3d.com/forum/index.php?webtag=MOI&msg=1774.22

I think that does everything you're asking about and with additional functionality as well (for the 3rd mode where you put in 2 distances and the item count is done for you).

- Michael