Nuprl Lemma : pair-lex_well_fnd

[A,B:Type]. ∀[Ra:A ⟶ A ⟶ ℙ]. ∀[Rb:B ⟶ B ⟶ ℙ].
  (WellFnd{i}(A;a1,a2.Ra a1 a2)  WellFnd{i}(B;b1,b2.Rb b1 b2)  WellFnd{i}(A × B;p1,p2.pair-lex(A;Ra;Rb) p1 p2))


Proof




Definitions occuring in Statement :  pair-lex: pair-lex(A;Ra;Rb) wellfounded: WellFnd{i}(A;x,y.R[x; y]) uall: [x:A]. B[x] prop: implies:  Q apply: a function: x:A ⟶ B[x] product: x:A × B[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T so_apply: x[s1;s2] implies:  Q wellfounded: WellFnd{i}(A;x,y.R[x; y]) all: x:A. B[x] pair-lex: pair-lex(A;Ra;Rb) pi1: fst(t) pi2: snd(t) subtype_rel: A ⊆B prop: so_lambda: λ2x.t[x] so_apply: x[s] and: P ∧ Q or: P ∨ Q so_lambda: λ2y.t[x; y]
Lemmas referenced :  product_well_fnd pair-lex_wf all_wf or_wf and_wf equal_wf wellfounded_wf
Rules used in proof :  cut lemma_by_obid sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation hypothesis sqequalHypSubstitution isectElimination thin hypothesisEquality sqequalRule lambdaFormation independent_functionElimination dependent_functionElimination productElimination applyEquality lambdaEquality universeEquality productEquality functionEquality spreadEquality cumulativity

Latex:
\mforall{}[A,B:Type].  \mforall{}[Ra:A  {}\mrightarrow{}  A  {}\mrightarrow{}  \mBbbP{}].  \mforall{}[Rb:B  {}\mrightarrow{}  B  {}\mrightarrow{}  \mBbbP{}].
    (WellFnd\{i\}(A;a1,a2.Ra  a1  a2)
    {}\mRightarrow{}  WellFnd\{i\}(B;b1,b2.Rb  b1  b2)
    {}\mRightarrow{}  WellFnd\{i\}(A  \mtimes{}  B;p1,p2.pair-lex(A;Ra;Rb)  p1  p2))



Date html generated: 2016_05_13-PM-03_18_37
Last ObjectModification: 2015_12_26-AM-09_06_51

Theory : well_fnd


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