Nuprl Lemma : adjacent-reverse

∀[T:Type]. ∀L:T List. ∀x,y:T.  (adjacent(T;rev(L);x;y) ⇐⇒ adjacent(T;L;y;x))


Proof




Definitions occuring in Statement :  adjacent: adjacent(T;L;x;y),  reverse: rev(as),  list: T List,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  member: t ∈ T,  so_lambda: λ2x.t[x],  so_apply: x[s],  implies: P ⇒ Q,  top: Top,  prop: ℙ,  iff: P ⇐⇒ Q,  and: P ∧ Q,  uimplies: b supposing a,  false: False,  rev_implies: P ⇐ Q,  decidable: Dec(P),  or: P ∨ Q,  assert: ↑b,  ifthenelse: if b then t else f fi ,  btrue: tt,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  cons: [a / b],  bfalse: ff,  not: ¬A,  guard: {T},  ge: i ≥ j ,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  cand: A c∧ B,  true: True,  append: as @ bs,  so_lambda: so_lambda(x,y,z.t[x; y; z]),  so_apply: x[s1;s2;s3],  le: A ≤ B
Lemmas referenced :  list_induction,  all_wf,  iff_wf,  adjacent_wf,  reverse_wf,  list_wf,  reverse_nil_lemma,  reverse-cons,  adjacent-nil,  nil_wf,  decidable__lt,  length_wf,  length-reverse,  list-cases,  null_nil_lemma,  length_of_nil_lemma,  product_subtype_list,  null_cons_lemma,  length_of_cons_lemma,  false_wf,  less_than_wf,  equal_wf,  reduce_hd_cons_lemma,  hd_wf,  decidable__le,  satisfiable-full-omega-tt,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  intformless_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_less_lemma,  int_formula_prop_wf,  last-reverse,  or_wf,  last_wf,  cons_wf,  adjacent-append,  append_wf,  itermAdd_wf,  int_term_value_add_lemma,  adjacent-cons,  adjacent-singleton,  list_ind_nil_lemma,  non_neg_length
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  thin,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  sqequalRule,  lambdaEquality,  cumulativity,  hypothesis,  independent_functionElimination,  rename,  isect_memberEquality,  voidElimination,  voidEquality,  because_Cache,  dependent_functionElimination,  universeEquality,  independent_pairFormation,  independent_isectElimination,  natural_numberEquality,  unionElimination,  productElimination,  imageElimination,  promote_hyp,  hypothesis_subsumption,  equalityTransitivity,  equalitySymmetry,  inrFormation,  productEquality,  dependent_pairFormation,  int_eqEquality,  intEquality,  computeAll,  inlFormation,  imageMemberEquality,  baseClosed,  addLevel,  impliesFunctionality,  addEquality

Latex:
\mforall{}[T:Type].  \mforall{}L:T  List.  \mforall{}x,y:T.    (adjacent(T;rev(L);x;y)  \mLeftarrow{}{}\mRightarrow{}  adjacent(T;L;y;x))



Date html generated: 2018_05_21-PM-06_39_13
Last ObjectModification: 2017_07_26-PM-04_53_18

Theory : general


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