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4 (* ||A|| A project by Andrea Asperti *)
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7 (* ||T|| The HELM team. *)
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15 include "basic_2/static/da.ma".
16 include "basic_2/static/aaa.ma".
18 (* ATONIC ARITY ASSIGNMENT FOR TERMS ****************************************)
20 (* Forward lemmas on degree assignment for terms ****************************)
22 lemma aaa_fwd_da: ∀h,g,G,L,T,A. ⦃G, L⦄ ⊢ T ⁝ A → ∃l. ⦃G, L⦄ ⊢ T ▪[h, g] l.
23 #h #g #G #L #T #A #H elim H -G -L -T -A
24 [ #G #L #k elim (deg_total … g k) /3 width=2/
25 | * #G #L #K [ #V | #W ] #B #i #HLK #_ * /3 width=5/
26 | #a #G #L #V #T #B #A #_ #_ #_ * /3 width=2/
27 | #a #G #L #V #T #B #A #_ #_ #_ * /3 width=2/
28 | #G #L #V #T #B #A #_ #_ #_ * /3 width=2/
29 | #G #L #W #T #A #_ #_ #_ * /3 width=2/