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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