thank you very much Old and Grey, you're very kind, but I'm not sure to have correctly understand.
for example for a 100 kg RM I must do:
:confused:
15 rep 3 workout with 42, 51, 60 kg
12 rep 3 workout with 45.5, 55.25, 65 kg
10 rep 3 workout with 49, 59.5, 70 kg
8 rep 3 workout with 52.5...