Nuprl Lemma : no_repeats_reverse

[T:Type]. ∀[L:T List].  uiff(no_repeats(T;rev(L));no_repeats(T;L))


Proof




Definitions occuring in Statement :  no_repeats: no_repeats(T;l) reverse: rev(as) list: List uiff: uiff(P;Q) uall: [x:A]. B[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uiff: uiff(P;Q) and: P ∧ Q uimplies: supposing a no_repeats: no_repeats(T;l) not: ¬A implies:  Q false: False top: Top nat: all: x:A. B[x] exists: x:A. B[x] subtype_rel: A ⊆B so_lambda: λ2x.t[x] so_apply: x[s] prop: sq_stable: SqStable(P) squash: T int_seg: {i..j-} lelt: i ≤ j < k le: A ≤ B true: True guard: {T} iff: ⇐⇒ Q rev_implies:  Q subtract: m sq_type: SQType(T) ge: i ≥  or: P ∨ Q nat_plus: + less_than: a < b less_than': less_than'(a;b) decidable: Dec(P)
Lemmas referenced :  length-reverse length_wf subtract_wf non_neg_length reverse_wf length_wf_nat nat_wf set_subtype_base le_wf int_subtype_base equal_wf select_wf sq_stable__le not_wf less_than_wf no_repeats_witness no_repeats_wf select-reverse lelt_wf iff_weakening_equal list_wf add-associates minus-one-mul add-swap add-commutes add-mul-special two-mul mul-distributes-right zero-mul zero-add one-mul subtype_base_sq not-equal-implies-less less-iff-le add_functionality_wrt_le le_reflexive minus-one-mul-top add-zero not-le-2 minus-zero omega-shadow mul-distributes mul-associates le-add-cancel not-lt-2 minus-add minus-minus nat_properties decidable__le decidable__lt squash_wf true_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut independent_pairFormation sqequalHypSubstitution lambdaFormation thin sqequalRule extract_by_obid isectElimination isect_memberEquality voidElimination voidEquality hypothesis because_Cache dependent_set_memberEquality cumulativity hypothesisEquality natural_numberEquality setElimination rename dependent_pairFormation sqequalIntensionalEquality applyEquality intEquality lambdaEquality independent_isectElimination equalityTransitivity equalitySymmetry dependent_functionElimination independent_functionElimination productElimination promote_hyp imageMemberEquality baseClosed imageElimination independent_pairEquality universeEquality addEquality multiplyEquality instantiate unionElimination minusEquality applyLambdaEquality

Latex:
\mforall{}[T:Type].  \mforall{}[L:T  List].    uiff(no\_repeats(T;rev(L));no\_repeats(T;L))



Date html generated: 2017_04_14-AM-08_40_54
Last ObjectModification: 2017_02_27-PM-03_32_24

Theory : list_0


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