On the possible resonant orbits of exoplanets

Within the framework of the restricted three-body problem, the possible orbits of a small-mass exoplanet in the system with a massive exoplanet on an elliptic orbit are investigated. Possible quasi-circular orbits are sought. The dependence of the Kozdai-Lidov effect (the Kozdai resonance) on the eccentricity of the orbit of a massive planet is discussed. The effect of the commensurabilities of the mean motions on the value of the eccentricity perturbations is considered.