Nuprl Lemma : length-list-delete

[T:Type]. ∀[as:T List]. ∀[i:ℕ].  ||as\i|| (||as|| 1) ∈ ℤ supposing i < ||as||


Proof




Definitions occuring in Statement :  list-delete: as\i length: ||as|| list: List nat: less_than: a < b uimplies: supposing a uall: [x:A]. B[x] subtract: m natural_number: $n int: universe: Type equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T so_lambda: λ2x.t[x] uimplies: supposing a nat: prop: so_apply: x[s] implies:  Q list-delete: as\i nil: [] it: subtract: m all: x:A. B[x] cons: [a b] top: Top so_lambda: λ2y.t[x; y] so_apply: x[s1;s2] false: False guard: {T} bool: 𝔹 unit: Unit btrue: tt uiff: uiff(P;Q) and: P ∧ Q less_than: a < b less_than': less_than'(a;b) true: True squash: T not: ¬A subtype_rel: A ⊆B bfalse: ff exists: x:A. B[x] or: P ∨ Q sq_type: SQType(T) bnot: ¬bb ifthenelse: if then else fi  assert: b decidable: Dec(P) iff: ⇐⇒ Q rev_implies:  Q le: A ≤ B nat_plus: +
Lemmas referenced :  list_induction uall_wf nat_wf isect_wf less_than_wf length_wf equal_wf list-delete_wf subtract_wf list_wf length_of_nil_lemma nil_wf length_of_cons_lemma spread_cons_lemma cons_wf less_than_transitivity1 less_than_irreflexivity lt_int_wf bool_wf eqtt_to_assert assert_of_lt_int top_wf add-associates add-swap add-commutes zero-add eqff_to_assert bool_cases_sqequal subtype_base_sq bool_subtype_base assert-bnot decidable__le false_wf not-le-2 not-lt-2 condition-implies-le minus-one-mul minus-one-mul-top minus-add minus-minus add_functionality_wrt_le le-add-cancel le_wf non_neg_length length_wf_nat set_subtype_base int_subtype_base less-iff-le le_reflexive one-mul add-mul-special two-mul mul-distributes-right zero-mul add-zero omega-shadow mul-distributes mul-associates mul-commutes le-add-cancel-alt squash_wf true_wf add_functionality_wrt_eq iff_weakening_equal nat_properties decidable__lt
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut thin extract_by_obid sqequalHypSubstitution isectElimination hypothesisEquality sqequalRule lambdaEquality hypothesis setElimination rename cumulativity intEquality because_Cache natural_numberEquality independent_functionElimination voidEquality isect_memberEquality axiomEquality equalityTransitivity equalitySymmetry lambdaFormation dependent_functionElimination voidElimination universeEquality independent_isectElimination unionElimination equalityElimination productElimination lessCases sqequalAxiom independent_pairFormation imageMemberEquality baseClosed imageElimination applyEquality minusEquality dependent_pairFormation promote_hyp instantiate dependent_set_memberEquality addEquality sqequalIntensionalEquality multiplyEquality

Latex:
\mforall{}[T:Type].  \mforall{}[as:T  List].  \mforall{}[i:\mBbbN{}].    ||as\mbackslash{}i||  =  (||as||  -  1)  supposing  i  <  ||as||



Date html generated: 2017_04_14-AM-08_55_37
Last ObjectModification: 2017_02_27-PM-03_39_30

Theory : omega


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