Nuprl Lemma : length-append

∀[as,bs:Top].  (||as @ bs|| ~ ||as|| + ||bs||)


Proof




Definitions occuring in Statement :  length: ||as||,  append: as @ bs,  uall: ∀[x:A]. B[x],  top: Top,  add: n + m,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  append: as @ bs,  length: ||as||,  so_lambda: λ2x.t[x],  so_apply: x[s],  uimplies: b supposing a,  strict1: strict1(F),  and: P ∧ Q,  all: ∀x:A. B[x],  implies: P ⇒ Q,  list_ind: list_ind,  has-value: (a)↓,  prop: ℙ,  or: P ∨ Q,  squash: ↓T,  guard: {T},  so_lambda: so_lambda(x,y,z.t[x; y; z]),  so_apply: x[s1;s2;s3],  top: Top
Lemmas referenced :  length-wf-has-value,  zero-add-base,  add-commutes,  add-associates,  top_wf,  sqle_wf_base,  length_of_cons_lemma,  int-value-type,  value-type-has-value,  is-exception_wf,  base_wf,  has-value_wf_base,  sqequal-list_ind
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalRule,  thin,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  baseClosed,  independent_isectElimination,  independent_pairFormation,  lambdaFormation,  callbyvalueCallbyvalue,  hypothesis,  callbyvalueReduce,  baseApply,  closedConclusion,  hypothesisEquality,  callbyvalueExceptionCases,  inlFormation,  imageMemberEquality,  imageElimination,  exceptionSqequal,  inrFormation,  callbyvalueAdd,  productElimination,  because_Cache,  equalityTransitivity,  equalitySymmetry,  addExceptionCases,  intEquality,  dependent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality,  sqequalAxiom,  natural_numberEquality,  divergentSqle,  sqleRule,  sqleReflexivity

Latex:
\mforall{}[as,bs:Top].    (||as  @  bs||  \msim{}  ||as||  +  ||bs||)



Date html generated: 2016_05_14-AM-06_35_06
Last ObjectModification: 2016_01_14-PM-08_23_09

Theory : list_0


Home Index