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Hopping Rabbit

CalcMedium~20 min· Probability
Problem

The Problem

A rabbit starts at position 0 on the integer lattice . At each step, it hops forward by an integer amount chosen uniformly from (think of it as rolling a die).

  1. What is the probability that the rabbit ever lands exactly on position (for large )?
  2. What is the expected number of hops to reach position or beyond?
  3. Generalize: if the hop distribution has mean and the rabbit starts at 0, what is the long-run probability of landing on any specific large ?