Nuprl Lemma : list_decomp_member

[T:Type]. ∀L:T List. ∀i:ℕ||L||.  ∃as,bs:T List. (L (as [L[i]] bs) ∈ (T List))


Proof




Definitions occuring in Statement :  select: L[n] length: ||as|| append: as bs cons: [a b] nil: [] list: List int_seg: {i..j-} uall: [x:A]. B[x] all: x:A. B[x] exists: x:A. B[x] natural_number: $n universe: Type equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] exists: x:A. B[x] member: t ∈ T int_seg: {i..j-} subtype_rel: A ⊆B uimplies: supposing a le: A ≤ B and: P ∧ Q less_than': less_than'(a;b) false: False not: ¬A implies:  Q prop: guard: {T} lelt: i ≤ j < k decidable: Dec(P) or: P ∨ Q less_than: a < b squash: T satisfiable_int_formula: satisfiable_int_formula(fmla) top: Top append: as bs so_lambda: so_lambda(x,y,z.t[x; y; z]) so_apply: x[s1;s2;s3] so_lambda: λ2x.t[x] so_apply: x[s] true: True int_iseg: {i...j} iff: ⇐⇒ Q rev_implies:  Q
Lemmas referenced :  firstn_wf nth_tl_wf nth_tl_decomp_eq int_seg_subtype_nat length_wf false_wf int_seg_properties decidable__lt satisfiable-full-omega-tt intformand_wf intformnot_wf intformless_wf itermVar_wf int_formula_prop_and_lemma int_formula_prop_not_lemma int_formula_prop_less_lemma int_term_value_var_lemma int_formula_prop_wf list_ind_cons_lemma list_ind_nil_lemma equal_wf list_wf append_wf cons_wf select_wf decidable__le intformle_wf itermConstant_wf int_formula_prop_le_lemma int_term_value_constant_lemma nil_wf exists_wf int_seg_wf subtype_rel_sets lelt_wf le_wf squash_wf true_wf iff_weakening_equal append_firstn_lastn
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation lambdaFormation dependent_pairFormation cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin cumulativity hypothesisEquality setElimination rename hypothesis addEquality natural_numberEquality because_Cache applyEquality independent_isectElimination sqequalRule independent_pairFormation productElimination dependent_functionElimination unionElimination imageElimination lambdaEquality int_eqEquality intEquality isect_memberEquality voidElimination voidEquality computeAll universeEquality productEquality setEquality applyLambdaEquality equalityTransitivity equalitySymmetry imageMemberEquality baseClosed independent_functionElimination

Latex:
\mforall{}[T:Type].  \mforall{}L:T  List.  \mforall{}i:\mBbbN{}||L||.    \mexists{}as,bs:T  List.  (L  =  (as  @  [L[i]]  @  bs))



Date html generated: 2017_04_14-AM-09_25_33
Last ObjectModification: 2017_02_27-PM-03_59_47

Theory : list_1


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