Nuprl Lemma : sum_switch

∀[n:ℕ]. ∀[f:ℕn ⟶ ℤ]. ∀[i:ℕn - 1].  (Σ(f[(i, i + 1) x] | x < n) = Σ(f[x] | x < n) ∈ ℤ)


Proof




Definitions occuring in Statement :  flip: (i, j),  sum: Σ(f[x] | x < k),  int_seg: {i..j-},  nat: ℕ,  uall: ∀[x:A]. B[x],  so_apply: x[s],  apply: f a,  function: x:A ⟶ B[x],  subtract: n - m,  add: n + m,  natural_number: $n,  int: ℤ,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  nat: ℕ,  int_seg: {i..j-},  lelt: i ≤ j < k,  and: P ∧ Q,  ge: i ≥ j ,  all: ∀x:A. B[x],  decidable: Dec(P),  or: P ∨ Q,  uimplies: b supposing a,  not: ¬A,  implies: P ⇒ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  top: Top,  prop: ℙ,  le: A ≤ B,  less_than: a < b,  squash: ↓T,  so_lambda: λ2x.t[x],  so_apply: x[s],  sq_type: SQType(T),  guard: {T},  less_than': less_than'(a;b),  subtype_rel: A ⊆r B,  nequal: a ≠ b ∈ T ,  assert: ↑b,  bnot: ¬bb,  bfalse: ff,  ifthenelse: if b then t else f fi ,  uiff: uiff(P;Q),  btrue: tt,  it: ⋅,  unit: Unit,  bool: 𝔹,  flip: (i, j),  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  lt_int: i <z j,  subtract: n - m,  true: True
Lemmas referenced :  int_seg_wf,  subtract_wf,  flip_wf,  nat_properties,  decidable__lt,  full-omega-unsat,  intformand_wf,  intformnot_wf,  intformless_wf,  itermVar_wf,  itermSubtract_wf,  itermConstant_wf,  istype-int,  int_formula_prop_and_lemma,  istype-void,  int_formula_prop_not_lemma,  int_formula_prop_less_lemma,  int_term_value_var_lemma,  int_term_value_subtract_lemma,  int_term_value_constant_lemma,  int_formula_prop_wf,  istype-le,  istype-less_than,  int_seg_properties,  decidable__le,  intformle_wf,  itermAdd_wf,  int_formula_prop_le_lemma,  int_term_value_add_lemma,  subtype_base_sq,  int_subtype_base,  sum_split,  lelt_wf,  false_wf,  int_seg_subtype_nat,  sum_functionality,  neg_assert_of_eq_int,  assert-bnot,  bool_subtype_base,  bool_cases_sqequal,  eqff_to_assert,  assert_of_eq_int,  eqtt_to_assert,  not_wf,  bnot_wf,  int_formula_prop_eq_lemma,  intformeq_wf,  equal_wf,  assert_wf,  equal-wf-T-base,  bool_wf,  eq_int_wf,  uiff_transitivity,  iff_transitivity,  iff_weakening_uiff,  assert_of_bnot,  primrec1_lemma,  squash_wf,  true_wf,  istype-universe,  add-comm,  subtype_rel_self,  iff_weakening_equal,  zero-add,  add-commutes,  sum-as-primrec,  primrec-unroll,  add-member-int_seg1,  le_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  introduction,  cut,  hypothesis,  Error :universeIsType,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  natural_numberEquality,  setElimination,  rename,  because_Cache,  sqequalRule,  Error :isect_memberEquality_alt,  hypothesisEquality,  axiomEquality,  Error :isectIsTypeImplies,  Error :inhabitedIsType,  Error :dependent_set_memberEquality_alt,  productElimination,  independent_pairFormation,  dependent_functionElimination,  unionElimination,  independent_isectElimination,  approximateComputation,  independent_functionElimination,  Error :dependent_pairFormation_alt,  Error :lambdaEquality_alt,  int_eqEquality,  voidElimination,  Error :productIsType,  addEquality,  imageElimination,  instantiate,  cumulativity,  intEquality,  applyEquality,  equalityTransitivity,  equalitySymmetry,  voidEquality,  isect_memberEquality,  dependent_pairFormation,  dependent_set_memberEquality,  functionExtensionality,  lambdaEquality,  lambdaFormation,  promote_hyp,  equalityElimination,  baseClosed,  impliesFunctionality,  Error :lambdaFormation_alt,  Error :equalityIstype,  universeEquality,  imageMemberEquality

Latex:
\mforall{}[n:\mBbbN{}].  \mforall{}[f:\mBbbN{}n  {}\mrightarrow{}  \mBbbZ{}].  \mforall{}[i:\mBbbN{}n  -  1].    (\mSigma{}(f[(i,  i  +  1)  x]  |  x  <  n)  =  \mSigma{}(f[x]  |  x  <  n))



Date html generated: 2019_06_20-PM-02_29_56
Last ObjectModification: 2019_02_06-PM-03_51_25

Theory : num_thy_1


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