Nuprl Lemma : iseg-append-nth_tl
∀[T:Type]. ∀[as,bs:T List].  (as @ nth_tl(||as||;bs)) = bs ∈ (T List) supposing as ≤ bs
Proof
Definitions occuring in Statement : 
iseg: l1 ≤ l2
, 
length: ||as||
, 
nth_tl: nth_tl(n;as)
, 
append: as @ bs
, 
list: T List
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
iseg: l1 ≤ l2
, 
exists: ∃x:A. B[x]
, 
prop: ℙ
, 
squash: ↓T
, 
true: True
Lemmas referenced : 
length_wf_nat, 
equal_wf, 
nat_wf, 
append_wf, 
squash_wf, 
true_wf, 
nth_tl_append, 
list_wf, 
nth_tl_wf, 
length_wf, 
iseg_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
sqequalHypSubstitution, 
productElimination, 
thin, 
dependent_set_memberEquality, 
hypothesis, 
extract_by_obid, 
isectElimination, 
cumulativity, 
hypothesisEquality, 
applyEquality, 
lambdaEquality, 
imageElimination, 
equalityTransitivity, 
equalitySymmetry, 
because_Cache, 
sqequalRule, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
hyp_replacement, 
Error :applyLambdaEquality, 
setElimination, 
rename, 
isect_memberEquality, 
axiomEquality, 
universeEquality
Latex:
\mforall{}[T:Type].  \mforall{}[as,bs:T  List].    (as  @  nth\_tl(||as||;bs))  =  bs  supposing  as  \mleq{}  bs
Date html generated:
2016_10_21-AM-10_35_19
Last ObjectModification:
2016_07_12-AM-05_47_23
Theory : list_1
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