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15 include "static_2/relocation/lifts_teqx.ma".
16 include "basic_2/rt_transition/cpx_drops_basic.ma".
17 include "basic_2/rt_transition/cnx.ma".
19 (* NORMAL TERMS FOR EXTENDED CONTEXT-SENSITIVE PARALLEL RT-TRANSITION *******)
21 (* Advanced inversion lemmas ************************************************)
23 lemma cnx_inv_abbr_pos (G) (L):
24 ∀V,T. ❪G,L❫ ⊢ ⬈𝐍 +ⓓV.T → ⊥.
26 elim (cpx_subst G (L.ⓓV) U1 … 0) [|*: /2 width=4 by drops_refl/ ] #U2 #T2 #HU12 #HTU2
27 elim (teqx_dec U1 U2) #HnU12 [ -HU12 | -HTU2 ]
28 [ elim (teqx_inv_lifts_dx … HnU12 … HTU2) -U2 #T1 #HTU1 #_ -T2
29 lapply (H T1 ?) -H [ /2 width=3 by cpx_zeta/ ] #H
30 /2 width=9 by teqx_lifts_inv_pair_sn/
31 | lapply (H (+ⓓV.U2) ?) -H [ /2 width=1 by cpx_bind/ ] -HU12 #H
32 elim (teqx_inv_pair … H) -H #_ #_ /2 width=1 by/