Nuprl Lemma : quicksort-int-null

∀[L:ℤ List]. uiff(↑null(quicksort-int(L));↑null(L))


Proof




Definitions occuring in Statement :  quicksort-int: quicksort-int(L),  null: null(as),  list: T List,  assert: ↑b,  uiff: uiff(P;Q),  uall: ∀[x:A]. B[x],  int: ℤ
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  rev_uimplies: rev_uimplies(P;Q),  all: ∀x:A. B[x],  subtype_rel: A ⊆r B,  prop: ℙ,  squash: ↓T,  true: True,  guard: {T},  iff: P ⇐⇒ Q,  implies: P ⇒ Q,  top: Top,  so_lambda: λ2x.t[x],  so_apply: x[s],  rev_implies: P ⇐ Q
Lemmas referenced :  assert_of_null,  quicksort-int_wf,  list_wf,  sorted-by_wf,  le_wf,  l_member_wf,  permutation_wf,  length_of_null_list,  equal_wf,  squash_wf,  true_wf,  quicksort-int-length,  iff_weakening_equal,  length_zero,  assert_witness,  null_wf3,  subtype_rel_list,  top_wf,  assert_wf,  subtype_rel_set,  quicksort-int-nil
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  independent_pairFormation,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  intEquality,  hypothesisEquality,  hypothesis,  productElimination,  independent_isectElimination,  dependent_functionElimination,  applyEquality,  lambdaEquality,  setElimination,  rename,  setEquality,  productEquality,  sqequalRule,  equalityTransitivity,  equalitySymmetry,  imageElimination,  universeEquality,  because_Cache,  natural_numberEquality,  imageMemberEquality,  baseClosed,  independent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairEquality,  lambdaFormation

Latex:
\mforall{}[L:\mBbbZ{}  List].  uiff(\muparrow{}null(quicksort-int(L));\muparrow{}null(L))



Date html generated: 2018_05_21-PM-07_35_14
Last ObjectModification: 2017_07_26-PM-05_09_29

Theory : general


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