Nuprl Lemma : wf-term-induction

∀[opr:Type]
  ∀sort:term(opr) ⟶ ℕ. ∀arity:opr ⟶ ((ℕ × ℕ) List).
    ∀[P:wfterm(opr;sort;arity) ⟶ ℙ]
      ((∀v:{v:varname()| ¬(v = nullvar() ∈ varname())} . P[varterm(v)])
      ⇒ (∀f:opr. ∀bts:wf-bound-terms(opr;sort;arity;f).  ((∀i:ℕ||bts||. P[snd(bts[i])]) ⇒ P[mkwfterm(f;bts)]))
      ⇒ {∀t:wfterm(opr;sort;arity). P[t]})


Proof




Definitions occuring in Statement :  mkwfterm: mkwfterm(f;bts),  wf-bound-terms: wf-bound-terms(opr;sort;arity;f),  wfterm: wfterm(opr;sort;arity),  varterm: varterm(v),  term: term(opr),  nullvar: nullvar(),  varname: varname(),  select: L[n],  length: ||as||,  list: T List,  int_seg: {i..j-},  nat: ℕ,  uall: ∀[x:A]. B[x],  prop: ℙ,  guard: {T},  so_apply: x[s],  pi2: snd(t),  all: ∀x:A. B[x],  not: ¬A,  implies: P ⇒ Q,  set: {x:A| B[x]} ,  function: x:A ⟶ B[x],  product: x:A × B[x],  natural_number: $n,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  all: ∀x:A. B[x],  guard: {T},  implies: P ⇒ Q,  so_apply: x[s],  wf-bound-terms: wf-bound-terms(opr;sort;arity;f),  prop: ℙ,  int_seg: {i..j-},  uimplies: b supposing a,  lelt: i ≤ j < k,  and: P ∧ Q,  le: A ≤ B,  less_than: a < b,  squash: ↓T,  decidable: Dec(P),  or: P ∨ Q,  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  pi2: snd(t),  assert: ↑b,  ifthenelse: if b then t else f fi ,  wf-term: wf-term(arity;sort;t),  varterm: varterm(v),  btrue: tt,  true: True,  wfterm: wfterm(opr;sort;arity)
Lemmas referenced :  term-ind_wf_wfterm,  wfterm_wf,  wf-bound-terms_wf,  int_seg_wf,  length_wf,  list_wf,  varname_wf,  select_wf,  int_seg_properties,  decidable__le,  full-omega-unsat,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  istype-int,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_wf,  decidable__lt,  intformless_wf,  int_formula_prop_less_lemma,  mkwfterm_wf,  nullvar_wf,  istype-void,  varterm_wf,  istype-assert,  wf-term_wf,  nat_wf,  term_wf,  istype-nat,  istype-universe
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  hypothesis,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  lambdaFormation_alt,  sqequalRule,  equalityTransitivity,  equalitySymmetry,  universeIsType,  functionIsType,  natural_numberEquality,  productEquality,  setElimination,  rename,  applyEquality,  functionExtensionality,  because_Cache,  independent_isectElimination,  productElimination,  imageElimination,  dependent_functionElimination,  unionElimination,  approximateComputation,  independent_functionElimination,  dependent_pairFormation_alt,  lambdaEquality_alt,  int_eqEquality,  Error :memTop,  independent_pairFormation,  voidElimination,  inhabitedIsType,  equalityIstype,  setIsType,  dependent_set_memberEquality_alt,  universeEquality,  instantiate

Latex:
\mforall{}[opr:Type]
    \mforall{}sort:term(opr)  {}\mrightarrow{}  \mBbbN{}.  \mforall{}arity:opr  {}\mrightarrow{}  ((\mBbbN{}  \mtimes{}  \mBbbN{})  List).
        \mforall{}[P:wfterm(opr;sort;arity)  {}\mrightarrow{}  \mBbbP{}]
            ((\mforall{}v:\{v:varname()|  \mneg{}(v  =  nullvar())\}  .  P[varterm(v)])
            {}\mRightarrow{}  (\mforall{}f:opr.  \mforall{}bts:wf-bound-terms(opr;sort;arity;f).
                        ((\mforall{}i:\mBbbN{}||bts||.  P[snd(bts[i])])  {}\mRightarrow{}  P[mkwfterm(f;bts)]))
            {}\mRightarrow{}  \{\mforall{}t:wfterm(opr;sort;arity).  P[t]\})



Date html generated: 2020_05_19-PM-09_58_56
Last ObjectModification: 2020_03_09-PM-04_10_28

Theory : terms


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