Nuprl Lemma : better-gcd-gcd

∀[y,x:ℤ].  (better-gcd(x;y) ~ gcd(x;y))


Proof




Definitions occuring in Statement :  better-gcd: better-gcd(a;b),  gcd: gcd(a;b),  uall: ∀[x:A]. B[x],  int: ℤ,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  sq_type: SQType(T),  all: ∀x:A. B[x],  implies: P ⇒ Q,  guard: {T},  nat: ℕ,  false: False,  ge: i ≥ j ,  prop: ℙ,  subtype_rel: A ⊆r B,  decidable: Dec(P),  or: P ∨ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  not: ¬A,  rev_implies: P ⇐ Q,  uiff: uiff(P;Q),  subtract: n - m,  top: Top,  le: A ≤ B,  less_than': less_than'(a;b),  true: True,  has-value: (a)↓,  nequal: a ≠ b ∈ T ,  gcd: gcd(a;b),  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  ifthenelse: if b then t else f fi ,  bfalse: ff,  better-gcd: better-gcd(a;b),  int_nzero: ℤ-o,  squash: ↓T
Lemmas referenced :  subtype_base_sq,  int_subtype_base,  nat_properties,  less_than_transitivity1,  less_than_irreflexivity,  ge_wf,  less_than_wf,  absval_wf,  decidable__le,  subtract_wf,  istype-false,  not-ge-2,  less-iff-le,  condition-implies-le,  minus-one-mul,  zero-add,  minus-one-mul-top,  istype-void,  minus-add,  minus-minus,  add-associates,  add-swap,  add-commutes,  add_functionality_wrt_le,  add-zero,  le-add-cancel,  nat_wf,  absval-non-neg,  eq_int_wf,  equal-wf-base,  bool_wf,  assert_wf,  bnot_wf,  not_wf,  value-type-has-value,  int-value-type,  uiff_transitivity,  eqtt_to_assert,  assert_of_eq_int,  iff_transitivity,  iff_weakening_uiff,  eqff_to_assert,  assert_of_bnot,  rem_bounds_z,  nequal_wf,  equal_wf,  squash_wf,  true_wf,  decidable__lt,  not-lt-2,  gcd_wf,  subtype_rel_self,  iff_weakening_equal,  zero-mul,  add-mul-special,  false_wf,  le_wf,  not-le-2
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  introduction,  cut,  thin,  instantiate,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  cumulativity,  intEquality,  independent_isectElimination,  hypothesis,  dependent_functionElimination,  equalityTransitivity,  equalitySymmetry,  independent_functionElimination,  axiomSqEquality,  Error :inhabitedIsType,  hypothesisEquality,  sqequalRule,  Error :isect_memberEquality_alt,  Error :universeIsType,  Error :lambdaFormation_alt,  setElimination,  rename,  intWeakElimination,  natural_numberEquality,  voidElimination,  Error :lambdaEquality_alt,  axiomEquality,  applyEquality,  because_Cache,  unionElimination,  independent_pairFormation,  productElimination,  addEquality,  minusEquality,  baseApply,  closedConclusion,  baseClosed,  Error :equalityIsType3,  callbyvalueReduce,  remainderEquality,  equalityElimination,  Error :equalityIsType1,  Error :dependent_set_memberEquality_alt,  imageElimination,  universeEquality,  imageMemberEquality,  multiplyEquality,  voidEquality,  isect_memberEquality,  lambdaEquality,  lambdaFormation,  dependent_set_memberEquality

Latex:
\mforall{}[y,x:\mBbbZ{}].    (better-gcd(x;y)  \msim{}  gcd(x;y))



Date html generated: 2019_06_20-AM-11_25_31
Last ObjectModification: 2018_09_28-AM-11_57_29

Theory : arithmetic


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