Convert a number to base 173

[Torbjorn Granlund]

    WARNING: remember that you must know what you are doing, when you use low
    level functions!

  Other ideas to resolve this?

You need to read the GMP manual carefully, then try hard yourself.
After that, and if you have specific questions, you will find
people on this list more than willing to help.

It is much more difficult to have people tell you how to write things,
when you have not acquired the basic GMP mpn knowledge from the manual.

-- 
Torbjörn