DEFINITION and4_rect()
TYPE =
       ΠP0:Prop
         .ΠP1:Prop
           .ΠP2:Prop
             .ΠP3:Prop
               .ΠP:(Type:47727:cic:/matita/LAMBDA-TYPES/Base-1/types/defs/and4_rect.con)
                 .(P0→P1→P2→P3→P)→(and4 P0 P1 P2 P3)→P
BODY =
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