Nuprl Lemma : isOdd-isEven-add

∀[n,m:ℤ].  (uiff(↑isOdd(n + m);¬↑same-parity(n;m)) ∧ uiff(↑isEven(n + m);↑same-parity(n;m)))


Proof




Definitions occuring in Statement :  same-parity: same-parity(n;m),  isEven: isEven(n),  isOdd: isOdd(n),  assert: ↑b,  uiff: uiff(P;Q),  uall: ∀[x:A]. B[x],  not: ¬A,  and: P ∧ Q,  add: n + m,  int: ℤ
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  and: P ∧ Q,  uiff: uiff(P;Q),  uimplies: b supposing a,  not: ¬A,  implies: P ⇒ Q,  false: False,  prop: ℙ,  cand: A c∧ B,  all: ∀x:A. B[x],  guard: {T},  top: Top,  subtract: n - m,  sq_type: SQType(T),  assert: ↑b,  ifthenelse: if b then t else f fi ,  btrue: tt,  true: True,  same-parity: same-parity(n;m),  bool: 𝔹,  unit: Unit,  it: ⋅,  bfalse: ff,  exists: ∃x:A. B[x],  or: P ∨ Q,  bnot: ¬bb,  isOdd: isOdd(n),  eq_int: (i =z j),  modulus: a mod n,  isEven: isEven(n),  absval: |i|
Lemmas referenced :  assert_wf,  same-parity_wf,  isOdd_wf,  assert_witness,  not_wf,  isEven_wf,  odd-implies,  general_add_assoc,  same-parity-implies,  add-subtract-cancel,  not-same-parity-implies,  even-implies,  add-associates,  add-swap,  add-commutes,  zero-add,  and_wf,  equal_wf,  assert_elim,  subtype_base_sq,  bool_wf,  bool_subtype_base,  add-zero,  eqtt_to_assert,  even-iff-not-odd,  eqff_to_assert,  bool_cases_sqequal,  assert-bnot,  bool_cases,  assert_of_bnot,  odd-iff-not-even,  subtract_wf,  subtract-add-cancel
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  intWeakElimination,  sqequalHypSubstitution,  thin,  rename,  hypothesis,  productElimination,  sqequalRule,  independent_pairEquality,  isect_memberEquality,  isectElimination,  hypothesisEquality,  lambdaEquality,  dependent_functionElimination,  voidElimination,  extract_by_obid,  addEquality,  equalityTransitivity,  equalitySymmetry,  independent_functionElimination,  natural_numberEquality,  because_Cache,  intEquality,  independent_pairFormation,  lambdaFormation,  independent_isectElimination,  voidEquality,  dependent_set_memberEquality,  applyLambdaEquality,  setElimination,  instantiate,  cumulativity,  hyp_replacement,  unionElimination,  equalityElimination,  dependent_pairFormation,  promote_hyp,  callbyvalueReduce,  sqleReflexivity,  minusEquality

Latex:
\mforall{}[n,m:\mBbbZ{}].    (uiff(\muparrow{}isOdd(n  +  m);\mneg{}\muparrow{}same-parity(n;m))  \mwedge{}  uiff(\muparrow{}isEven(n  +  m);\muparrow{}same-parity(n;m)))



Date html generated: 2017_04_17-AM-09_43_48
Last ObjectModification: 2017_02_27-PM-05_38_43

Theory : num_thy_1


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