[gmantastic]

Addition and comparison will suffice: https://gist.github.com/garethjwilliams/7202128

[deletes]

Awesome solution, but it breaks if you change the iteration range.

[gmantastic]

Yeah, you're stuck with counting up from 1, although you could tweak it to suppress the output prior to a starting point.

[deletes]

Here is my C solution for arbitrary positive range: http://ideone.com/a0EdtS

[gmantastic]

Nice, I get it. Here's mine tweaked - not so clever: https://gist.github.com/garethjwilliams/7210264