Nuprl Lemma : comb_for_firstn_wf

λA,as,n,z. firstn(n;as) ∈ A:Type ⟶ as:(A List) ⟶ n:ℤ ⟶ (↓True) ⟶ (A List)


Proof




Definitions occuring in Statement :  firstn: firstn(n;as),  list: T List,  squash: ↓T,  true: True,  member: t ∈ T,  lambda: λx.A[x],  function: x:A ⟶ B[x],  int: ℤ,  universe: Type
Definitions unfolded in proof :  member: t ∈ T,  squash: ↓T,  uall: ∀[x:A]. B[x],  prop: ℙ
Lemmas referenced :  firstn_wf,  squash_wf,  true_wf,  istype-int,  list_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :lambdaEquality_alt,  sqequalHypSubstitution,  imageElimination,  cut,  introduction,  extract_by_obid,  isectElimination,  thin,  hypothesisEquality,  equalityTransitivity,  hypothesis,  equalitySymmetry,  Error :universeIsType,  universeEquality

Latex:
\mlambda{}A,as,n,z.  firstn(n;as)  \mmember{}  A:Type  {}\mrightarrow{}  as:(A  List)  {}\mrightarrow{}  n:\mBbbZ{}  {}\mrightarrow{}  (\mdownarrow{}True)  {}\mrightarrow{}  (A  List)



Date html generated: 2019_06_20-PM-00_43_10
Last ObjectModification: 2018_10_01-PM-00_27_54

Theory : list_0


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