Am 08.02.11 09:37 schrieb Juergen Fenn: > But unfortunately I did not get any code snippets from there, I have to correct this: You get the LaTeX source by simply copy and pasting the formulae... it's as simple as that, e.g.: Let {X n d }n≥0be a uniform symmetric random walk on Zd, and Π(d) (a,b)={X n d ∈ Zd : a ≤ n ≤ b}. Suppose f(n) is an integer-valued function on n and increases to infinity as n↑∞, and let $$E_n^{\left( d \right)} = \left\{ {\prod {^{\left( d \right)} } \left( {0,n} \right) \cap \prod {^{\left( d \right)} } \left( {n + f\left( n \right),\infty } \right) \ne \emptyset } \right\}$$ Estimates on the probability of the event $$E_n^{\left( d \right)} $$ are obtained for $$d \geqq 3$$ . As an application, a necessary and sufficient condition to ensure $$P\left( {E_n^{\left( d \right)} ,{\text{i}}{\text{.o}}{\text{.}}} \right) = 0\quad {\text{or}}\quad {\text{1}}$$ is derived for $$d \geqq 3$$ . These extend some results obtained by Erdős and Taylor about the self-intersections of the simple random walk on Zd. Regards, Jürgen.