Nuprl Lemma : equipollent-multiply

∀a,b:ℕ.  ℕa × ℕb ~ ℕa * b


Proof




Definitions occuring in Statement :  equipollent: A ~ B,  int_seg: {i..j-},  nat: ℕ,  all: ∀x:A. B[x],  product: x:A × B[x],  multiply: n * m,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  equipollent: A ~ B,  exists: ∃x:A. B[x],  member: t ∈ T,  uall: ∀[x:A]. B[x],  int_seg: {i..j-},  nat: ℕ,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  lelt: i ≤ j < k,  le: A ≤ B,  less_than: a < b,  squash: ↓T,  prop: ℙ,  top: Top,  satisfiable_int_formula: satisfiable_int_formula(fmla),  or: P ∨ Q,  decidable: Dec(P),  ge: i ≥ j ,  guard: {T},  implies: P ⇒ Q,  not: ¬A,  false: False,  less_than': less_than'(a;b),  subtype_rel: A ⊆r B,  biject: Bij(A;B;f),  inject: Inj(A;B;f),  so_lambda: λ2x.t[x],  so_apply: x[s],  surject: Surj(A;B;f),  nat_plus: ℕ+,  div_nrel: Div(a;n;q),  sq_type: SQType(T),  int_nzero: ℤ-o,  nequal: a ≠ b ∈ T ,  subtract: n - m,  true: True,  rev_implies: P ⇐ Q,  iff: P ⇐⇒ Q
Lemmas referenced :  add-member-int_seg1,  istype-le,  subtract_wf,  istype-less_than,  int_seg_wf,  biject_wf,  istype-nat,  int_term_value_mul_lemma,  itermMultiply_wf,  int_formula_prop_wf,  int_formula_prop_less_lemma,  int_term_value_constant_lemma,  int_term_value_subtract_lemma,  int_term_value_var_lemma,  int_formula_prop_le_lemma,  int_formula_prop_not_lemma,  int_formula_prop_and_lemma,  istype-int,  intformless_wf,  itermConstant_wf,  itermSubtract_wf,  itermVar_wf,  intformle_wf,  intformnot_wf,  intformand_wf,  full-omega-unsat,  decidable__le,  nat_properties,  int_seg_properties,  mul_preserves_le,  istype-void,  int_seg_subtype_nat,  mul_bounds_1a,  decidable__lt,  set_subtype_base,  le_wf,  int_subtype_base,  product_subtype_base,  lelt_wf,  div_unique,  istype-false,  int_term_value_add_lemma,  itermAdd_wf,  int_formula_prop_eq_lemma,  intformeq_wf,  less_than_wf,  decidable__equal_int,  subtype_base_sq,  remainder_wfa,  nequal_wf,  rem_bounds_1,  minus-zero,  minus-add,  add-commutes,  condition-implies-le,  le-add-cancel,  zero-add,  add-zero,  add-associates,  add_functionality_wrt_le,  not-equal-2,  not-lt-2,  div_rem_sum,  div_bounds_1,  false_wf,  multiply-is-int-iff,  add-is-int-iff
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :lambdaFormation_alt,  Error :dependent_pairFormation_alt,  Error :lambdaEquality_alt,  productElimination,  thin,  sqequalRule,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  multiplyEquality,  setElimination,  rename,  hypothesisEquality,  hypothesis,  closedConclusion,  natural_numberEquality,  because_Cache,  independent_isectElimination,  Error :dependent_set_memberEquality_alt,  independent_pairFormation,  Error :productIsType,  imageElimination,  Error :universeIsType,  productEquality,  Error :inhabitedIsType,  voidElimination,  Error :isect_memberEquality_alt,  int_eqEquality,  independent_functionElimination,  approximateComputation,  unionElimination,  dependent_functionElimination,  applyEquality,  Error :equalityIstype,  baseApply,  baseClosed,  intEquality,  sqequalBase,  equalitySymmetry,  equalityTransitivity,  applyLambdaEquality,  addEquality,  independent_pairEquality,  cumulativity,  instantiate,  minusEquality,  divideEquality,  promote_hyp,  pointwiseFunctionality

Latex:
\mforall{}a,b:\mBbbN{}.    \mBbbN{}a  \mtimes{}  \mBbbN{}b  \msim{}  \mBbbN{}a  *  b



Date html generated: 2019_06_20-PM-02_17_08
Last ObjectModification: 2019_06_19-PM-06_34_45

Theory : equipollence!!cardinality!


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