Nuprl Lemma : l_exists_reduce
∀[T:Type]. ∀L:T List. ∀P:T ⟶ 𝔹.  ((∃x∈L. ↑P[x]) 
⇐⇒ ↑reduce(λx,y. (P[x] ∨by);ff;L))
Proof
Definitions occuring in Statement : 
l_exists: (∃x∈L. P[x])
, 
reduce: reduce(f;k;as)
, 
list: T List
, 
bor: p ∨bq
, 
assert: ↑b
, 
bfalse: ff
, 
bool: 𝔹
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
lambda: λx.A[x]
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
member: t ∈ T
, 
so_lambda: λ2x.t[x]
, 
prop: ℙ
, 
so_apply: x[s]
, 
implies: P 
⇒ Q
, 
top: Top
, 
assert: ↑b
, 
ifthenelse: if b then t else f fi 
, 
bfalse: ff
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
rev_implies: P 
⇐ Q
, 
guard: {T}
, 
lelt: i ≤ j < k
, 
int_seg: {i..j-}
, 
exists: ∃x:A. B[x]
, 
false: False
, 
so_apply: x[s1;s2]
, 
so_lambda: λ2x y.t[x; y]
, 
it: ⋅
, 
nil: []
, 
uimplies: b supposing a
, 
select: L[n]
, 
l_exists: (∃x∈L. P[x])
, 
uiff: uiff(P;Q)
, 
rev_uimplies: rev_uimplies(P;Q)
, 
or: P ∨ Q
Lemmas referenced : 
list_induction, 
all_wf, 
bool_wf, 
iff_wf, 
l_exists_wf, 
l_member_wf, 
assert_wf, 
reduce_wf, 
bor_wf, 
bfalse_wf, 
reduce_nil_lemma, 
istype-void, 
reduce_cons_lemma, 
list_wf, 
assert_of_bor, 
assert_witness, 
l_exists_cons, 
cons_wf, 
length_of_nil_lemma, 
stuck-spread, 
base_wf, 
less_than_transitivity1, 
less_than_irreflexivity, 
exists_wf, 
int_seg_wf, 
false_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
Error :isect_memberFormation_alt, 
Error :lambdaFormation_alt, 
cut, 
thin, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
hypothesisEquality, 
sqequalRule, 
Error :lambdaEquality_alt, 
functionEquality, 
cumulativity, 
hypothesis, 
because_Cache, 
Error :universeIsType, 
setElimination, 
rename, 
applyEquality, 
functionExtensionality, 
Error :setIsType, 
Error :functionIsType, 
independent_functionElimination, 
dependent_functionElimination, 
Error :isect_memberEquality_alt, 
voidElimination, 
Error :inhabitedIsType, 
Error :productIsType, 
universeEquality, 
lambdaEquality, 
natural_numberEquality, 
productElimination, 
independent_pairFormation, 
voidEquality, 
isect_memberEquality, 
lambdaFormation, 
independent_isectElimination, 
baseClosed, 
lemma_by_obid, 
unionElimination, 
Error :inlFormation_alt, 
Error :inrFormation_alt, 
Error :unionIsType, 
promote_hyp
Latex:
\mforall{}[T:Type].  \mforall{}L:T  List.  \mforall{}P:T  {}\mrightarrow{}  \mBbbB{}.    ((\mexists{}x\mmember{}L.  \muparrow{}P[x])  \mLeftarrow{}{}\mRightarrow{}  \muparrow{}reduce(\mlambda{}x,y.  (P[x]  \mvee{}\msubb{}y);ff;L))
Date html generated:
2019_06_20-PM-00_41_22
Last ObjectModification:
2018_10_02-PM-06_03_53
Theory : list_0
Home
Index