October 2, 2006
For any recurrent random walk (S_n)_{n>0} on R, there are increasing sequences (g_n)_{n>0} converging to infinity for which (g_n S_n)_{n>0} has at least one finite accumulation point. For one class of random walks, we give a criterion on (g_n)_{n>0} and the distribution of S_1 determining the set of accumulation points for (g_n S_n)_{n>0}. This extends, with a simpler proof, a result of K.L. Chung and P. Erdos. Finally, for recurrent, symmetric random walks, we give a criterion characterizing the increasing sequences (g_n)_{n>0} of positive numbers for which liminf g_n|S_n|=0.
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