## 3 Discussion and Conclusions
We considered seismicity patterns obtained by an identical simulation algorithm applied to two different seismogenic sources, namely a unique large fault system constituted by the subduction interface in Southwestern Japan (NMTFS) and a complex seismogenic system consisting of 43 fault systems with various kinematics in Central Italy (CNAFS). The results of the comparison have shown a striking similarity in the features of the seismicity patterns of the two different geodynamic contexts, except for a relevant difference in their time scale. This similarity derives from the fact that the features of the earthquake catalogues produced by the simulator are controlled by the algorithm adopted in the simulator for the two fault systems in the same way. The faster behavior of the NMTFS compared to that of the CNAFS reflects the ratio between the slip rates of their sources. We do not have the mechanistic explanations of the seismicity patterns obtained from our simulation algorithm, except for the fact that it behaves as a kind of self-organized system mimicking the vastly more complex real self-organized seismogenic systems. Figure 5: Number of events obtained from the stacking procedure, in logarithmic scale, versus the magnitude of the pivot events for the CNAFS (**a**) and the NMTFS (**b**). The color is determined by normalizing each line to its total number of events. This normalization compensates for the decreasing frequency of higher-magnitude pivot events, providing a clearer representation of event trends. The question of whether a simulation algorithm reliably represents the real long-term seismogenic process is difficult to answer because the available real observations are of too short a duration to provide significant statistical results. The Italian historical catalogue, even if it is one of the longest in the world, barely contains more than one characteristic earthquake for a single fault system, due to the long average time between two subsequent maximum events generated by the same source (DISS Working Group 2021 [25]). The circumstance that all four strongest earthquakes reported in Table 1 for the CNAFS in the last 10 centuries occurred in the last 3 centuries, could generate some thoughts on the completeness and homogeneity of the historical catalogue. This circumstance has a probability smaller than 1% of occurring by chance under the hypothesis of a random Poisson time distribution. A test carried out on the 100,000-year simulated catalogue of the CNAFS has shown that a similar clustering effect occurs in an extremely small number of cases and for slightly larger M\({}_{\text{th}}\). Therefore, the hypothesis of a variation in the seismicity rate generated by large-scale clustering and a consequence of fault interaction cannot be discarded (in agreement with [PERSON] et al., 2022 [15]). Also, for the historical earthquake catalogue regarding the NMTFS, even if it contains information on some characteristic earthquakes ([PERSON] et al., 2012 [20]), their limited number, the uncertainty on the fault segments ruptured in each earthquake, and the lack of information about events of a smaller size prevent a significant comparison with the seismicity patterns exhibited by the simulated catalogue. A possible way of assessing the reliability of simulated catalogues seems to be focusing on short-term seismicity patterns as foreshock sequences and aftershock decay rates, for which the instrumental observations can provide large catalogues going down to small magnitudes. One of these patterns is, for instance, the above-mentioned short-term precursory change in the b-value, which has been observed in real catalogues. A simulation exhibiting this pattern has already been published in Figure 8 of [PERSON] et al. (2022) [15].