I was first sent a math/programming test to solve from home. After passing the test I was interviewed three times over the phone. I got rejected after the third interview. I thought the written exam was fairly complex, but doable. The first two interviews went well, but the third one did not. I couldn't understand what the interviewer was saying so I didn't properly answer some of his questions (I am not a native english speaker, and neither was he).

Two technical phone interviews then in-person interview. On the first phone interview, interviewer asked about randomly positioned points on a circle, then to step through an analysis of Buffon's Needle. On the second phone interview, interviewer asked about a gambling game which was sort-of inverse Prisoner's Dilemma with repeated playings