Same as in Fig. 6, but for the system Kepler-31. Only analytical maps are shown in this case since in some simulations capture into resonance was unsuccessful due to overstability of the captured state for different planetary mass ratios. As explained in the text, this issue is model-dependent and is not within the scope of our analysis. Moreover, inthe simulations where capture was successful, the results agree well with the analytical calculations, showing . Comparing with Fig. 9 we see that there is a ~20% probability that Kepler-31 lies this close to the 2:1 – 2:1 chain by pure chance.