Nuprl Lemma : firstn_append_front

[L1:Top List]. ∀L2:Top List. (firstn(||L1 L2|| ||L2||;L1 L2) L1)


Proof




Definitions occuring in Statement :  firstn: firstn(n;as) length: ||as|| append: as bs list: List uall: [x:A]. B[x] top: Top all: x:A. B[x] subtract: m sqequal: t
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T all: x:A. B[x] int_seg: {i..j-} lelt: i ≤ j < k and: P ∧ Q squash: T prop: true: True subtype_rel: A ⊆B uimplies: supposing a guard: {T} iff: ⇐⇒ Q rev_implies:  Q implies:  Q ge: i ≥  decidable: Dec(P) or: P ∨ Q le: A ≤ B satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] false: False not: ¬A top: Top
Lemmas referenced :  firstn_all add-subtract-cancel lelt_wf int_formula_prop_less_lemma intformless_wf decidable__lt length-append int_formula_prop_wf int_term_value_var_lemma int_term_value_add_lemma int_term_value_subtract_lemma int_term_value_constant_lemma int_formula_prop_le_lemma int_formula_prop_not_lemma int_formula_prop_and_lemma itermVar_wf itermAdd_wf itermSubtract_wf itermConstant_wf intformle_wf intformnot_wf intformand_wf satisfiable-full-omega-tt decidable__le non_neg_length iff_weakening_equal length_append true_wf squash_wf le_wf append_wf length_wf subtract_wf firstn_append top_wf list_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut lambdaFormation hypothesis lemma_by_obid sqequalHypSubstitution isectElimination thin sqequalRule lambdaEquality dependent_functionElimination hypothesisEquality sqequalAxiom because_Cache dependent_set_memberEquality independent_pairFormation applyEquality imageElimination equalityTransitivity equalitySymmetry intEquality natural_numberEquality imageMemberEquality baseClosed universeEquality independent_isectElimination productElimination independent_functionElimination unionElimination dependent_pairFormation int_eqEquality isect_memberEquality voidElimination voidEquality computeAll addEquality

Latex:
\mforall{}[L1:Top  List].  \mforall{}L2:Top  List.  (firstn(||L1  @  L2||  -  ||L2||;L1  @  L2)  \msim{}  L1)



Date html generated: 2016_05_14-PM-02_08_24
Last ObjectModification: 2016_01_15-AM-08_02_20

Theory : list_1


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