Nuprl Lemma : permr_hd_cancel

∀T:Type. ∀a:T. ∀bs,bs':T List.  (([a / bs] ≡(T) [a / bs']) ⇒ (bs ≡(T) bs'))


Proof




Definitions occuring in Statement :  permr: as ≡(T) bs,  cons: [a / b],  list: T List,  all: ∀x:A. B[x],  implies: P ⇒ Q,  universe: Type
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  prop: ℙ,  uall: ∀[x:A]. B[x],  permr: as ≡(T) bs,  cand: A c∧ B,  exists: ∃x:A. B[x],  top: Top,  ge: i ≥ j ,  decidable: Dec(P),  or: P ∨ Q,  le: A ≤ B,  and: P ∧ Q,  uimplies: b supposing a,  satisfiable_int_formula: satisfiable_int_formula(fmla),  false: False,  not: ¬A,  int_seg: {i..j-},  lelt: i ≤ j < k,  guard: {T},  uiff: uiff(P;Q),  subtract: n - m,  nat_plus: ℕ+,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  true: True,  sym_grp: Sym(n),  so_lambda: λ2x.t[x],  perm: Perm(T),  subtype_rel: A ⊆r B,  nat: ℕ,  so_apply: x[s],  inv_funs: InvFuns(A;B;f;g),  tidentity: Id{T},  compose: f o g,  identity: Id,  perm_morph: perm_morph(S;T;s2t;t2s;p),  mk_perm: mk_perm(f;b),  perm_f: p.f,  pi1: fst(t),  tl_perm: tl_perm(p),  comp_perm: comp_perm,  txpose_perm: txpose_perm,  swap: swap(i;j),  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  ifthenelse: if b then t else f fi ,  bfalse: ff,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  sq_type: SQType(T),  select: L[n],  cons: [a / b]
Lemmas referenced :  permr_wf,  cons_wf,  list_wf,  length_of_cons_lemma,  non_neg_length,  decidable__equal_int,  length_wf,  satisfiable-full-omega-tt,  intformand_wf,  intformnot_wf,  intformeq_wf,  itermVar_wf,  itermAdd_wf,  itermConstant_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_eq_lemma,  int_term_value_var_lemma,  int_term_value_add_lemma,  int_term_value_constant_lemma,  int_formula_prop_wf,  perm_morph_wf,  int_seg_wf,  subtract_wf,  int_seg_properties,  decidable__le,  intformle_wf,  itermSubtract_wf,  int_formula_prop_le_lemma,  int_term_value_subtract_lemma,  decidable__lt,  intformless_wf,  int_formula_prop_less_lemma,  lelt_wf,  add-member-int_seg2,  tl_perm_wf,  add_nat_plus,  length_wf_nat,  less_than_wf,  nat_plus_wf,  nat_plus_properties,  equal_wf,  all_wf,  select_wf,  perm_f_wf,  nat_properties,  subtract-add-cancel,  add-subtract-cancel,  eq_int_wf,  bool_wf,  equal-wf-T-base,  assert_wf,  bnot_wf,  not_wf,  perm_b_wf,  false_wf,  uiff_transitivity,  eqtt_to_assert,  assert_of_eq_int,  iff_transitivity,  iff_weakening_uiff,  eqff_to_assert,  assert_of_bnot,  equal_symmetry,  perm_b_to_f,  perm_f_inj,  subtype_base_sq,  set_subtype_base,  int_subtype_base,  squash_wf,  true_wf,  select-cons-tl,  add-is-int-iff,  equal-wf-base-T,  equal-wf-base,  select_cons_tl,  iff_weakening_equal
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  cumulativity,  hypothesisEquality,  isectElimination,  hypothesis,  universeEquality,  productElimination,  independent_pairFormation,  sqequalRule,  isect_memberEquality,  voidElimination,  voidEquality,  because_Cache,  unionElimination,  natural_numberEquality,  independent_isectElimination,  dependent_pairFormation,  lambdaEquality,  int_eqEquality,  intEquality,  computeAll,  equalityTransitivity,  equalitySymmetry,  dependent_set_memberEquality,  setElimination,  rename,  addEquality,  independent_functionElimination,  imageMemberEquality,  baseClosed,  applyLambdaEquality,  applyEquality,  equalityElimination,  impliesFunctionality,  instantiate,  hyp_replacement,  imageElimination,  pointwiseFunctionality,  promote_hyp,  baseApply,  closedConclusion

Latex:
\mforall{}T:Type.  \mforall{}a:T.  \mforall{}bs,bs':T  List.    (([a  /  bs]  \mequiv{}(T)  [a  /  bs'])  {}\mRightarrow{}  (bs  \mequiv{}(T)  bs'))



Date html generated: 2017_10_01-AM-09_54_18
Last ObjectModification: 2017_03_03-PM-00_56_00

Theory : perms_2


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