Nuprl Lemma : alpha-rename-alist-nonnullvar

∀[opr:Type]
  ∀t:term(opr). ∀L:varname() List. ∀x,x':varname().
    ((<x, x'> ∈ alpha-rename-alist(t;L)) ⇒ (x' = nullvar() ∈ varname()) ⇒ (nullvar() ∈ L))


Proof




Definitions occuring in Statement :  alpha-rename-alist: alpha-rename-alist(t;L),  term: term(opr),  nullvar: nullvar(),  varname: varname(),  l_member: (x ∈ l),  list: T List,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  pair: <a, b>,  product: x:A × B[x],  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  alpha-rename-alist: alpha-rename-alist(t;L),  member: t ∈ T,  so_lambda: λ2x y.t[x; y],  has-value: (a)↓,  uimplies: b supposing a,  varname: varname(),  so_lambda: λ2x.t[x],  so_apply: x[s],  so_apply: x[s1;s2],  guard: {T},  prop: ℙ,  implies: P ⇒ Q,  pi2: snd(t),  and: P ∧ Q,  nil: [],  it: ⋅,  not: ¬A,  false: False,  iff: P ⇐⇒ Q,  or: P ∨ Q,  pi1: fst(t),  squash: ↓T,  true: True,  subtype_rel: A ⊆r B,  rev_implies: P ⇐ Q
Lemmas referenced :  list_accum_invariant2,  varname_wf,  list_wf,  value-type-has-value,  bunion-value-type,  nat_wf,  atom-value-type,  product-value-type,  istype-atom,  maybe_new_var_wf,  cons_wf,  l_member_wf,  pi2_wf,  equal-wf-T-base,  nullvar_wf,  append_wf,  all-vars_wf,  nil_wf,  null_nil_lemma,  btrue_wf,  null_wf,  member-implies-null-eq-bfalse,  btrue_neq_bfalse,  cons_member,  pi1_wf,  term_wf,  istype-universe,  maybe_new_var-is-null,  squash_wf,  true_wf,  subtype_rel_self,  iff_weakening_equal
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  lambdaFormation_alt,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesis,  productEquality,  dependent_functionElimination,  sqequalRule,  lambdaEquality_alt,  productElimination,  callbyvalueReduce,  independent_isectElimination,  atomEquality,  because_Cache,  hypothesisEquality,  independent_pairEquality,  closedConclusion,  universeIsType,  productIsType,  functionEquality,  inhabitedIsType,  baseClosed,  independent_functionElimination,  voidEquality,  equalitySymmetry,  dependent_set_memberEquality_alt,  independent_pairFormation,  equalityTransitivity,  equalityIstype,  applyLambdaEquality,  setElimination,  rename,  voidElimination,  unionElimination,  functionIsType,  instantiate,  universeEquality,  applyEquality,  imageElimination,  natural_numberEquality,  imageMemberEquality

Latex:
\mforall{}[opr:Type]
    \mforall{}t:term(opr).  \mforall{}L:varname()  List.  \mforall{}x,x':varname().
        ((<x,  x'>  \mmember{}  alpha-rename-alist(t;L))  {}\mRightarrow{}  (x'  =  nullvar())  {}\mRightarrow{}  (nullvar()  \mmember{}  L))



Date html generated: 2020_05_19-PM-09_57_15
Last ObjectModification: 2020_03_09-PM-04_09_37

Theory : terms


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