DEFINITION pc3_fsubst0()
TYPE =
       c1:C
         .t1:T
           .t:T
             .pc3 c1 t1 t
               i:nat
                    .u:T.c2:C.t2:T.(fsubst0 i u c1 t1 c2 t2)e:C.(getl i c1 (CHead e (Bind Abbr) u))(pc3 c2 t2 t)
BODY =
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