Nuprl Lemma : lsum-of-even
∀[T:Type]. ∀[L:T List]. ∀[f:{x:T| (x ∈ L)}  ⟶ ℤ].  ↑isEven(Σ(f[x] | x ∈ L)) supposing (∀x∈L.↑isEven(f[x]))
Proof
Definitions occuring in Statement : 
isEven: isEven(n)
, 
lsum: Σ(f[x] | x ∈ L)
, 
l_all: (∀x∈L.P[x])
, 
l_member: (x ∈ l)
, 
list: T List
, 
assert: ↑b
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
set: {x:A| B[x]} 
, 
function: x:A ⟶ B[x]
, 
int: ℤ
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
, 
nat: ℕ
, 
implies: P 
⇒ Q
, 
false: False
, 
ge: i ≥ j 
, 
uimplies: b supposing a
, 
not: ¬A
, 
satisfiable_int_formula: satisfiable_int_formula(fmla)
, 
exists: ∃x:A. B[x]
, 
top: Top
, 
and: P ∧ Q
, 
prop: ℙ
, 
guard: {T}
, 
or: P ∨ Q
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
assert: ↑b
, 
ifthenelse: if b then t else f fi 
, 
isEven: isEven(n)
, 
eq_int: (i =z j)
, 
modulus: a mod n
, 
remainder: n rem m
, 
btrue: tt
, 
true: True
, 
subtype_rel: A ⊆r B
, 
cons: [a / b]
, 
le: A ≤ B
, 
less_than': less_than'(a;b)
, 
colength: colength(L)
, 
nil: []
, 
it: ⋅
, 
sq_type: SQType(T)
, 
less_than: a < b
, 
squash: ↓T
, 
so_lambda: λ2x y.t[x; y]
, 
so_apply: x[s1;s2]
, 
decidable: Dec(P)
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
l_member: (x ∈ l)
, 
select: L[n]
, 
cand: A c∧ B
, 
nat_plus: ℕ+
, 
uiff: uiff(P;Q)
, 
rev_uimplies: rev_uimplies(P;Q)
, 
same-parity: same-parity(n;m)
, 
bool: 𝔹
, 
unit: Unit
, 
bfalse: ff
, 
bnot: ¬bb
Lemmas referenced : 
nat_properties, 
full-omega-unsat, 
intformand_wf, 
intformle_wf, 
itermConstant_wf, 
itermVar_wf, 
intformless_wf, 
istype-int, 
int_formula_prop_and_lemma, 
istype-void, 
int_formula_prop_le_lemma, 
int_term_value_constant_lemma, 
int_term_value_var_lemma, 
int_formula_prop_less_lemma, 
int_formula_prop_wf, 
ge_wf, 
istype-less_than, 
assert_witness, 
intformeq_wf, 
int_formula_prop_eq_lemma, 
list-cases, 
lsum_nil_lemma, 
isEven_wf, 
l_all_wf_nil, 
assert_wf, 
l_member_wf, 
nil_wf, 
product_subtype_list, 
colength-cons-not-zero, 
colength_wf_list, 
istype-le, 
lsum_wf, 
subtract-1-ge-0, 
subtype_base_sq, 
set_subtype_base, 
int_subtype_base, 
spread_cons_lemma, 
decidable__equal_int, 
subtract_wf, 
intformnot_wf, 
itermSubtract_wf, 
itermAdd_wf, 
int_formula_prop_not_lemma, 
int_term_value_subtract_lemma, 
int_term_value_add_lemma, 
decidable__le, 
le_wf, 
lsum_cons_lemma, 
subtype_rel_dep_function, 
cons_wf, 
subtype_rel_sets_simple, 
cons_member, 
l_all_cons, 
length_of_cons_lemma, 
add_nat_plus, 
length_wf_nat, 
decidable__lt, 
nat_plus_properties, 
add-is-int-iff, 
false_wf, 
length_wf, 
select_wf, 
list-subtype, 
subtype_rel_list, 
subtype_rel_sets, 
l_all_wf, 
istype-nat, 
list_wf, 
istype-universe, 
isEven-add, 
eqtt_to_assert, 
eqff_to_assert, 
bool_cases_sqequal, 
bool_wf, 
bool_subtype_base
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
cut, 
thin, 
lambdaFormation_alt, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
hypothesisEquality, 
hypothesis, 
setElimination, 
rename, 
intWeakElimination, 
natural_numberEquality, 
independent_isectElimination, 
approximateComputation, 
independent_functionElimination, 
dependent_pairFormation_alt, 
lambdaEquality_alt, 
int_eqEquality, 
dependent_functionElimination, 
isect_memberEquality_alt, 
voidElimination, 
sqequalRule, 
independent_pairFormation, 
universeIsType, 
equalityTransitivity, 
equalitySymmetry, 
applyLambdaEquality, 
isectIsTypeImplies, 
inhabitedIsType, 
functionIsTypeImplies, 
unionElimination, 
applyEquality, 
dependent_set_memberEquality_alt, 
because_Cache, 
functionIsType, 
setIsType, 
promote_hyp, 
hypothesis_subsumption, 
productElimination, 
equalityIstype, 
instantiate, 
imageElimination, 
baseApply, 
closedConclusion, 
baseClosed, 
intEquality, 
sqequalBase, 
setEquality, 
inrFormation_alt, 
pointwiseFunctionality, 
productIsType, 
addEquality, 
universeEquality, 
equalityElimination, 
cumulativity
Latex:
\mforall{}[T:Type].  \mforall{}[L:T  List].  \mforall{}[f:\{x:T|  (x  \mmember{}  L)\}    {}\mrightarrow{}  \mBbbZ{}].
    \muparrow{}isEven(\mSigma{}(f[x]  |  x  \mmember{}  L))  supposing  (\mforall{}x\mmember{}L.\muparrow{}isEven(f[x]))
Date html generated:
2020_05_19-PM-10_01_34
Last ObjectModification:
2019_11_13-AM-10_10_24
Theory : num_thy_1
Home
Index