BuG cRYPTO cRACKME

[bLaCk-eye]

Hello everybody
Here is a very nice crypto crackme made by myself some weeks ago.
Not really crypto but more of a math crackme.Quite challenging i might say : 5/10.
Hope it's interesting and fun to tackle...
LINK:
http://www.crackmes.de/users/black_eye/bug_crypto_crackme/download
Best wishes,

bLaCk