  We obtain the exact expression for the matrix of nonadiabatic transition
probabilities in the model of three interacting states with a time-dependent
Hamiltonian. Unlike other known solvable Landau-Zener-like problems, our
solution is generally expressed in terms of hypergeometric functions that have
relatively complex behavior, e.g. the obtained transition probabilities may
show multiple oscillations as functions of parameters of the model Hamiltonian.
