Nuprl Lemma : nat2inf-one-one

∀[a,b:ℕ].  ((a∞ = b∞ ∈ ℕ∞) ⇒ (a = b ∈ ℕ))


Proof




Definitions occuring in Statement :  nat2inf: n∞,  nat-inf: ℕ∞,  nat: ℕ,  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  implies: P ⇒ Q,  nat2inf: n∞,  nat-inf: ℕ∞,  uimplies: b supposing a,  sq_type: SQType(T),  all: ∀x:A. B[x],  guard: {T},  not: ¬A,  nat: ℕ,  uiff: uiff(P;Q),  and: P ∧ Q,  prop: ℙ,  ge: i ≥ j ,  decidable: Dec(P),  or: P ∨ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  top: Top
Lemmas referenced :  subtype_base_sq,  bool_wf,  bool_subtype_base,  assert_of_lt_int,  less_than_wf,  nat_properties,  decidable__equal_int,  satisfiable-full-omega-tt,  intformand_wf,  intformnot_wf,  intformeq_wf,  itermVar_wf,  intformless_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_eq_lemma,  int_term_value_var_lemma,  int_formula_prop_less_lemma,  int_formula_prop_wf,  decidable__le,  intformle_wf,  itermConstant_wf,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  le_wf,  equal_wf,  nat-inf_wf,  nat2inf_wf,  nat_wf,  assert_wf,  lt_int_wf,  not_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lambdaFormation,  sqequalHypSubstitution,  applyLambdaEquality,  applyEquality,  setElimination,  thin,  rename,  hypothesisEquality,  hypothesis,  sqequalRule,  instantiate,  extract_by_obid,  isectElimination,  cumulativity,  independent_isectElimination,  dependent_functionElimination,  equalityTransitivity,  equalitySymmetry,  independent_functionElimination,  productElimination,  promote_hyp,  unionElimination,  natural_numberEquality,  dependent_pairFormation,  lambdaEquality,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  computeAll,  dependent_set_memberEquality,  because_Cache,  axiomEquality,  addLevel,  impliesFunctionality

Latex:
\mforall{}[a,b:\mBbbN{}].    ((a\minfty{}  =  b\minfty{})  {}\mRightarrow{}  (a  =  b))



Date html generated: 2017_10_01-AM-08_29_17
Last ObjectModification: 2017_07_26-PM-04_23_54

Theory : basic


Home Index