Problem:
Caboyara, a famous Australian circus performer, once again this year performs a great trick. He sets up a spectacular staircase with steps, where are distinct prime numbers; the steps corresponding to divisors of (including the first and the -th step) are special and are initially lit up green.
During the show, 2015 trained kangaroos climb the staircase one after another; for , the -th kangaroo jumps steps at a time, starting from the foot of the staircase (it jumps onto step , then onto , and so on until it reaches step ). Every time a kangaroo jumps onto a special step, it changes color: from green it becomes red, from red it becomes green.
How many special steps will be lit up green at the end of the performance?