Nuprl Lemma : unzip-zip
∀[as,bs:Top List].  unzip(zip(as;bs)) ~ <as, bs> supposing ||as|| = ||bs|| ∈ ℤ
Proof
Definitions occuring in Statement : 
unzip: unzip(as)
, 
zip: zip(as;bs)
, 
length: ||as||
, 
list: T List
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
top: Top
, 
pair: <a, b>
, 
int: ℤ
, 
sqequal: s ~ t
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
unzip: unzip(as)
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
subtype_rel: A ⊆r B
, 
nat: ℕ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
Lemmas referenced : 
map-fst-zip, 
map-snd-zip, 
istype-int, 
length_wf_nat, 
top_wf, 
set_subtype_base, 
le_wf, 
int_subtype_base, 
list_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation_alt, 
introduction, 
cut, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
independent_isectElimination, 
hypothesis, 
axiomSqEquality, 
equalityIstype, 
applyEquality, 
intEquality, 
lambdaEquality_alt, 
natural_numberEquality, 
sqequalBase, 
equalitySymmetry, 
isect_memberEquality_alt, 
isectIsTypeImplies, 
inhabitedIsType, 
universeIsType
Latex:
\mforall{}[as,bs:Top  List].    unzip(zip(as;bs))  \msim{}  <as,  bs>  supposing  ||as||  =  ||bs||
Date html generated:
2020_05_19-PM-09_50_26
Last ObjectModification:
2020_02_27-PM-04_06_06
Theory : list_1
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