Nuprl Lemma : empty-bag-union
∀T:Type. ∀bs:bag(bag(T)).  ((bag-union(bs) = {} ∈ bag(T)) ⇒ (bs ~ bag-rep(#(bs);{})))
Proof
Definitions occuring in Statement : 
bag-rep: bag-rep(n;x), 
bag-union: bag-union(bbs), 
bag-size: #(bs), 
empty-bag: {}, 
bag: bag(T), 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
universe: Type, 
sqequal: s ~ t, 
equal: s = t ∈ T
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
member: t ∈ T, 
prop: ℙ, 
uall: ∀[x:A]. B[x], 
bag-rep: bag-rep(n;x), 
concat: concat(ll), 
cons-bag: x.b, 
empty-bag: {}, 
nat: ℕ, 
false: False, 
ge: i ≥ j , 
uimplies: b supposing a, 
satisfiable_int_formula: satisfiable_int_formula(fmla), 
exists: ∃x:A. B[x], 
not: ¬A, 
top: Top, 
and: P ∧ Q, 
subtype_rel: A ⊆r B, 
guard: {T}, 
or: P ∨ Q, 
cons: [a / b], 
colength: colength(L), 
so_lambda: λ2x y.t[x; y], 
so_apply: x[s1;s2], 
decidable: Dec(P), 
nil: [], 
it: ⋅, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
sq_type: SQType(T), 
less_than: a < b, 
squash: ↓T, 
less_than': less_than'(a;b), 
bool: 𝔹, 
unit: Unit, 
btrue: tt, 
uiff: uiff(P;Q), 
ifthenelse: if b then t else f fi , 
le: A ≤ B, 
bfalse: ff, 
bnot: ¬bb, 
assert: ↑b, 
bag-size: #(bs), 
bag: bag(T), 
quotient: x,y:A//B[x; y], 
true: True, 
bag-union: bag-union(bbs), 
bag-append: as + bs, 
iff: P ⇐⇒ Q, 
int_seg: {i..j-}, 
lelt: i ≤ j < k, 
rev_implies: P ⇐ Q
Lemmas referenced : 
equal-wf-T-base, 
bag_wf, 
bag-union_wf, 
nil_wf, 
top_wf, 
nat_properties, 
satisfiable-full-omega-tt, 
intformand_wf, 
intformle_wf, 
itermConstant_wf, 
itermVar_wf, 
intformless_wf, 
int_formula_prop_and_lemma, 
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, 
less_than_wf, 
list_wf, 
reduce_wf, 
append_wf, 
nat_wf, 
colength_wf_list, 
less_than_transitivity1, 
less_than_irreflexivity, 
list-cases, 
reduce_nil_lemma, 
length_of_nil_lemma, 
primrec0_lemma, 
equal-wf-base, 
product_subtype_list, 
spread_cons_lemma, 
intformeq_wf, 
itermAdd_wf, 
int_formula_prop_eq_lemma, 
int_term_value_add_lemma, 
decidable__le, 
intformnot_wf, 
int_formula_prop_not_lemma, 
le_wf, 
equal_wf, 
subtract_wf, 
itermSubtract_wf, 
int_term_value_subtract_lemma, 
subtype_base_sq, 
set_subtype_base, 
int_subtype_base, 
decidable__equal_int, 
reduce_cons_lemma, 
length_of_cons_lemma, 
primrec-unroll, 
length_wf, 
eq_int_wf, 
bool_wf, 
eqtt_to_assert, 
assert_of_eq_int, 
non_neg_length, 
eqff_to_assert, 
bool_cases_sqequal, 
bool_subtype_base, 
assert-bnot, 
neg_assert_of_eq_int, 
append_is_nil, 
null_nil_lemma, 
btrue_wf, 
and_wf, 
null_wf, 
null_cons_lemma, 
bfalse_wf, 
btrue_neq_bfalse, 
add-subtract-cancel, 
permutation_wf, 
permutation_weakening, 
subtype_rel_list, 
bag-subtype-list, 
member_wf, 
squash_wf, 
true_wf, 
permutation-length, 
list_extensionality, 
l_member_wf, 
bag-append_wf, 
empty-bag_wf, 
member-implies-null-eq-bfalse, 
cons_wf, 
bag-append-is-empty, 
cons_member, 
equal-empty-bag, 
equal-nil-sq-nil, 
select_wf, 
select_member, 
lelt_wf, 
decidable__lt, 
member-permutation, 
l_member_subtype
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
cut, 
hypothesis, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
cumulativity, 
hypothesisEquality, 
baseClosed, 
universeEquality, 
sqequalRule, 
setElimination, 
rename, 
intWeakElimination, 
natural_numberEquality, 
independent_isectElimination, 
dependent_pairFormation, 
lambdaEquality, 
int_eqEquality, 
intEquality, 
dependent_functionElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
independent_pairFormation, 
computeAll, 
independent_functionElimination, 
sqequalAxiom, 
applyEquality, 
because_Cache, 
unionElimination, 
promote_hyp, 
hypothesis_subsumption, 
productElimination, 
equalityTransitivity, 
equalitySymmetry, 
applyLambdaEquality, 
dependent_set_memberEquality, 
addEquality, 
instantiate, 
imageElimination, 
equalityElimination, 
pointwiseFunctionality, 
pertypeElimination, 
productEquality, 
imageMemberEquality, 
comment, 
hyp_replacement
Latex:
\mforall{}T:Type.  \mforall{}bs:bag(bag(T)).    ((bag-union(bs)  =  \{\})  {}\mRightarrow{}  (bs  \msim{}  bag-rep(\#(bs);\{\})))
Date html generated:
2017_10_01-AM-08_52_10
Last ObjectModification:
2017_07_26-PM-04_33_50
Theory : bags
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