Upper panel: D_n(4000) index vs. stellar mass for the cluster A2142. Red circles indicate low star formation rate galaxies with log SFR < −0.5, and blue circles shows high star formation rate galaxies with log SFR ≥ −0.5. Other notations are as in Fig. 5. Lower panels: probability density distributions of D_n (4000) (left), and stellar mass (right) of galaxies in the main cluster (black solid line), in the outskirts component C2 (subclusters M1–M3 taken together, black dashed line), and in subclusters M1–M3 (M1 – violet line, M2 – aquamarine line, and M3 – orange line).