My assumption is that you refer to the RC Spread Footing design module. These combinations are automatically generated. In fact Robot generates two sets of them; one for RC part design and one for 'geotechnical' part (sizing of a foundation).
EC7_04_A1 refer to the A1 set from the table A.3 from Appendix A
EC7_04_A2 to A2
In the geotechnical options the 18.104.22.168.4 approach is selected.
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