Nuprl Lemma : finite-type-list
∀[T:Type]. ((∀x,y:T.  Dec(x = y ∈ T)) 
⇒ (∀L:T List. finite-type({x:T| (x ∈ L)} )))
Proof
Definitions occuring in Statement : 
finite-type: finite-type(T)
, 
l_member: (x ∈ l)
, 
list: T List
, 
decidable: Dec(P)
, 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
set: {x:A| B[x]} 
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
implies: P 
⇒ Q
, 
all: ∀x:A. B[x]
, 
member: t ∈ T
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
Lemmas referenced : 
cardinality-le-finite, 
l_member_wf, 
length_wf_nat, 
list_wf, 
all_wf, 
decidable_wf, 
equal_wf, 
cardinality-le-list-set
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
lambdaFormation, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
setEquality, 
hypothesisEquality, 
hypothesis, 
dependent_functionElimination, 
independent_functionElimination, 
sqequalRule, 
lambdaEquality, 
universeEquality
Latex:
\mforall{}[T:Type].  ((\mforall{}x,y:T.    Dec(x  =  y))  {}\mRightarrow{}  (\mforall{}L:T  List.  finite-type(\{x:T|  (x  \mmember{}  L)\}  )))
Date html generated:
2016_05_14-PM-03_31_44
Last ObjectModification:
2015_12_26-PM-06_01_41
Theory : decidable!equality
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