DEFINITION tlt_wf_ind()
TYPE =
∀P:T→Prop.(∀t:T.(∀v:T.(tlt v t)→(P v))→(P t))→∀t:T.(P t)
BODY =
(Q)
assume P: T→Prop
assume n: nat
assume t: T
suppose : eq nat (weight t) n
by (. .)
we proved
suppose : eq nat (weight t) n
by (. .)
we proved
by (. .)
we proved
end of Q
assume P: T→Prop
suppose H: ∀t:T.(∀v:T.(lt (weight v) (weight t))→(P v))→(P t)
assume t: T
assume n: nat
assume n0: nat
suppose H0: ∀m:nat.(lt m n0)→(Q λt0:T.P t0 m)
we must prove Q λt0:T.P t0 n0
or equivalently ∀t0:T.(eq nat (weight t0) n0)→(P t0)
assume t0: T
suppose H1: eq nat (weight t0) n0
(H2)
consider H0
we proved ∀m:nat.(lt m n0)→(Q λt0:T.P t0 m)
that is equivalent to ∀m:nat.(lt m n0)→∀t1:T.(eq nat (weight t1) m)→(P t1)
by (eq_ind_r . . . previous . H1)
∀m:nat.(lt m (weight t0))→∀t1:T.(eq nat (weight t1) m)→(P t1)
end of H2
assume v: T
suppose H3: lt (weight v) (weight t0)
by (refl_equal . .)
we proved eq nat (weight v) (weight v)
by (H2 . H3 . previous)
we proved P v
we proved ∀v:T.(lt (weight v) (weight t0))→(P v)
by (H . previous)
we proved P t0
we proved ∀t0:T.(eq nat (weight t0) n0)→(P t0)
that is equivalent to Q λt0:T.P t0 n0
we proved ∀n0:nat.(∀m:nat.(lt m n0)→(Q λt0:T.P t0 m))→(Q λt0:T.P t0 n0)
by (lt_wf_ind . . previous)
we proved Q λt0:T.P t0 n
that is equivalent to ∀t:T.(eq nat (weight t) n)→(P t)
we proved ∀n:nat.∀t:T.(eq nat (weight t) n)→(P t)
by (tlt_wf__q_ind . previous .)
we proved P t
we proved
∀P:T→Prop
.∀t:T.(∀v:T.(lt (weight v) (weight t))→(P v))→(P t)
→∀t:T.(P t)
that is equivalent to
∀P:T→Prop.(∀t:T.(∀v:T.(tlt v t)→(P v))→(P t))→∀t:T.(P t)