I toss a balanced coin until the number of heads I get equals the number of tails? What's the chance I never stop?
I have tried considering the reverse event and a recursive reasoning but nothing conclusive. A close question has already been asked here but I don't know the Markov formalism that is used.
Th probability is zero that you will continue forever. The Wikipedia article on the random walk cites the result that with probability $1$ you will visit any specific point on the number line, which includes zero, but does not prove it.