摘要
Let be the simple random walk in zd, and SupPers f(n) is an integer-valued function and increases to infinity as n tends to infinity, and In this paper,a necessary and sufficient condition to ensure or 1 is derived for d=3,4. This problem was first studied by P. Erdos and S.J. Taylor.
Let be the simple random walk in zd, and SupPers f(n) is an integer-valued function and increases to infinity as n tends to infinity, and In this paper,a necessary and sufficient condition to ensure or 1 is derived for d=3,4. This problem was first studied by P. Erdos and S.J. Taylor.
