Zhdanova Yu. D.
Ukr. Mat. Zh. - 1993. - 45, № 3. - pp. 361–366
For the classical ruin problem (a special case of a cyclic group), we use an explicit expression for the characteristic function of the time of first hitting an arbitrary subset of a finite solvable group by a random walk, “from” a fixed subset, to obtain a new proof of the well-known formula which allows one to estimate the characteristic function of the ruin probability (hitting the identity of a group) at the th- trial.
Ukr. Mat. Zh. - 1989. - 41, № 10. - pp. 1395–1398
Ukr. Mat. Zh. - 1989. - 41, № 9. - pp. 1204–1207