Nuprl Lemma : stream-lex-iff
∀T:Type. ∀R:T ⟶ T ⟶ ℙ. ∀s1,s2:stream(T).
  (s1 stream-lex(T;R) s2 
⇐⇒ (s-hd(s1) R s-hd(s2)) ∧ ((s-hd(s1) = s-hd(s2) ∈ T) 
⇒ (s-tl(s1) stream-lex(T;R) s-tl(s2))))
Proof
Definitions occuring in Statement : 
stream-lex: stream-lex(T;R)
, 
s-tl: s-tl(s)
, 
s-hd: s-hd(s)
, 
stream: stream(A)
, 
prop: ℙ
, 
infix_ap: x f y
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
implies: P 
⇒ Q
, 
and: P ∧ Q
, 
function: x:A ⟶ B[x]
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
so_lambda: λ2x.t[x]
, 
infix_ap: x f y
, 
implies: P 
⇒ Q
, 
prop: ℙ
, 
so_apply: x[s]
, 
stream-lex: stream-lex(T;R)
, 
rel_implies: R1 => R2
, 
and: P ∧ Q
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
cand: A c∧ B
, 
guard: {T}
, 
rel-monotone: rel-monotone{i:l}(T;R.F[R])
, 
rel-continuous: rel-continuous{i:l}(T;R.F[R])
, 
isect-rel: isect-rel(T;i.R[i])
, 
nat: ℕ
, 
le: A ≤ B
, 
less_than': less_than'(a;b)
, 
false: False
, 
not: ¬A
Lemmas referenced : 
bigrel-iff, 
and_wf, 
s-hd_wf, 
equal_wf, 
s-tl_wf, 
stream_wf, 
stream-lex_wf, 
all_wf, 
nat_wf, 
false_wf, 
le_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
because_Cache, 
dependent_functionElimination, 
sqequalRule, 
lambdaEquality, 
applyEquality, 
hypothesisEquality, 
hypothesis, 
functionEquality, 
cumulativity, 
universeEquality, 
independent_functionElimination, 
productElimination, 
independent_pairFormation, 
dependent_set_memberEquality, 
natural_numberEquality
Latex:
\mforall{}T:Type.  \mforall{}R:T  {}\mrightarrow{}  T  {}\mrightarrow{}  \mBbbP{}.  \mforall{}s1,s2:stream(T).
    (s1  stream-lex(T;R)  s2
    \mLeftarrow{}{}\mRightarrow{}  (s-hd(s1)  R  s-hd(s2))  \mwedge{}  ((s-hd(s1)  =  s-hd(s2))  {}\mRightarrow{}  (s-tl(s1)  stream-lex(T;R)  s-tl(s2))))
Date html generated:
2016_05_14-AM-06_24_02
Last ObjectModification:
2015_12_26-AM-11_58_36
Theory : co-recursion
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