Project Euler Problem 1 functionally

I'm trying to learn a bit of elisp (see Luhns Algorithm in elisp). So, to try out me elisp some more I tried the Project Euler's simplest problem, Problem 1. So, I cracked open emacs and tried out a few things, gave up and went into hibernation. A few weeks later I remembered this problem and had a go at it again. I thought I nailed it... After a bit of googling I found out the elisp only supports 300 recursive calls :(. So, I decided to take the plunge into clisp and started downloading that. Meanwhile I had some old version of scala available and tried this Wow, that went well and by the time I had googled to find the syntax for scala etc., clisp was downloaded and here goes https://gist.github.com/fc-unleashed/86ecd9aee76dcd8ec1decb3f15b84d6d