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Resonant interactions between ions and Alfv\'en/ion-cyclotron (A/IC) wavesmay play an important role in the heating and acceleration of the fast solarwind. Although such interactions have been studied extensively for "parallel"waves, whose wave vectors ${\bf k}$ are aligned with the background magneticfield ${\bf B}_0$, much less is known about interactions between ions andoblique A/IC waves, for which the angle $\theta$ between ${\bf k}$ and ${\bfB}_0$ is nonzero. In this paper, we present new numerical results on resonantcyclotron interactions between protons and oblique A/IC waves in collisionlesslow-beta plasmas such as the solar corona. We find that if some mechanismgenerates oblique high-frequency A/IC waves, then these waves initially modifythe proton distribution function in such a way that it becomes unstable toparallel waves. Parallel waves are then amplified to the point that theydominate the wave energy at the large parallel wave numbers at which the wavesresonate with the particles. Pitch-angle scattering by these waves then causesthe plasma to evolve towards a state in which the proton distribution isconstant along a particular set of nested "scattering surfaces" in velocityspace, whose shapes have been calculated previously. As the distributionfunction approaches this state, the imaginary part of the frequency of parallelA/IC waves drops continuously towards zero, but oblique waves continue toundergo cyclotron damping while simultaneously causing protons to diffuseacross these kinetic shells to higher energies. We conclude that oblique A/ICwaves can be more effective at heating protons than parallel A/IC waves,because for oblique waves the plasma does not relax towards a state in whichproton damping of oblique A/IC waves ceases.

Resonant Interactions Between Protons and Oblique Alfv\'en/Ion-Cyclotron Waves