Abstract
For a one-dimensional simple random walk (S_t), for each time t we say a site x is a favorite site if it has the maximal local time. In this talk, we show that with probability 1 three favorite sites occurs infinitely often. Our work is inspired by T\'oth (2001), and disproves a conjecture of Erd\"{o}s and R\'ev\'esz (1984) and of T\'oth (2001). Joint work with Jianfei Shen.