Nuprl Lemma : fix_wf_corec
∀[F:Type ⟶ Type]. ∀[G:⋂T:Type. (T ⟶ F[T])].  (fix(G) ∈ corec(T.F[T]))
Proof
Definitions occuring in Statement : 
corec: corec(T.F[T])
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
member: t ∈ T
, 
fix: fix(F)
, 
isect: ⋂x:A. B[x]
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
uimplies: b supposing a
, 
strong-type-continuous: Continuous+(T.F[T])
, 
type-continuous: Continuous(T.F[T])
, 
isect2: T1 ⋂ T2
, 
bool: 𝔹
, 
unit: Unit
, 
it: ⋅
, 
btrue: tt
, 
ifthenelse: if b then t else f fi 
, 
bfalse: ff
, 
top: Top
Lemmas referenced : 
fix_wf_corec2, 
continuous-id, 
subtype_rel_self, 
nat_wf, 
top_wf, 
bool_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
sqequalRule, 
lambdaEquality, 
universeEquality, 
independent_isectElimination, 
hypothesis, 
isectEquality, 
applyEquality, 
functionEquality, 
cumulativity, 
isect_memberEquality, 
unionElimination, 
equalityElimination, 
equalityTransitivity, 
equalitySymmetry, 
functionExtensionality, 
voidElimination, 
voidEquality, 
axiomEquality, 
because_Cache
Latex:
\mforall{}[F:Type  {}\mrightarrow{}  Type].  \mforall{}[G:\mcap{}T:Type.  (T  {}\mrightarrow{}  F[T])].    (fix(G)  \mmember{}  corec(T.F[T]))
Date html generated:
2016_05_14-AM-06_19_10
Last ObjectModification:
2015_12_26-PM-00_02_35
Theory : co-recursion
Home
Index