DEFINITION ty3_inv_lref_nf2_pc3()
TYPE =
       g:G
         .c:C
           .u1:T
             .i:nat
               .ty3 g c (TLRef i) u1
                 (nf2 c (TLRef i)
                      u2:T.(nf2 c u2)(pc3 c u1 u2)(ex T λu:T.eq T u2 (lift (S i) O u)))
BODY =
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