Nuprl Lemma : cons-not-nil

∀[S:Type]. ∀[a:S]. ∀[b:S List].  (¬([a / b] = [] ∈ (S List)))


Proof




Definitions occuring in Statement :  cons: [a / b],  nil: [],  list: T List,  uall: ∀[x:A]. B[x],  not: ¬A,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  not: ¬A,  implies: P ⇒ Q,  false: False
Lemmas referenced :  cons_neq_nil,  cons_wf,  list_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  introduction,  cut,  Error :lambdaFormation_alt,  thin,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  hypothesis,  independent_functionElimination,  voidElimination,  Error :equalityIsType3,  Error :inhabitedIsType,  baseClosed,  sqequalRule,  Error :lambdaEquality_alt,  dependent_functionElimination,  because_Cache,  Error :universeIsType,  Error :isect_memberEquality_alt,  universeEquality

Latex:
\mforall{}[S:Type].  \mforall{}[a:S].  \mforall{}[b:S  List].    (\mneg{}([a  /  b]  =  []))



Date html generated: 2019_06_20-PM-00_40_26
Last ObjectModification: 2018_09_30-PM-11_01_37

Theory : list_0


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