Nuprl Lemma : non-empty-bag-union-of-list

[T:Type]. ∀L:bag(T) List. (0 < #(bag-union(L)) ⇐⇒ (∃b∈L. 0 < #(b)))


Proof




Definitions occuring in Statement :  bag-union: bag-union(bbs) bag-size: #(bs) bag: bag(T) l_exists: (∃x∈L. P[x]) list: List less_than: a < b uall: [x:A]. B[x] all: x:A. B[x] iff: ⇐⇒ Q natural_number: $n universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] member: t ∈ T so_lambda: λ2x.t[x] subtype_rel: A ⊆B uimplies: supposing a nat: prop: so_apply: x[s] implies:  Q bag-size: #(bs) bag-union: bag-union(bbs) concat: concat(ll) top: Top iff: ⇐⇒ Q and: P ∧ Q false: False less_than: a < b squash: T less_than': less_than'(a;b) rev_implies:  Q bag-append: as bs or: P ∨ Q decidable: Dec(P) guard: {T} ge: i ≥  satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] not: ¬A nat_plus: + uiff: uiff(P;Q)
Lemmas referenced :  list_induction bag_wf iff_wf less_than_wf bag-size_wf bag-union_wf list-subtype-bag subtype_rel_self nat_wf l_exists_wf l_member_wf list_wf reduce_nil_lemma length_of_nil_lemma false_wf l_exists_nil l_exists_wf_nil reduce_cons_lemma bag-size-append l_exists_cons cons_wf or_wf decidable__lt nat_properties satisfiable-full-omega-tt intformand_wf intformle_wf itermConstant_wf itermVar_wf intformnot_wf intformless_wf itermAdd_wf int_formula_prop_and_lemma int_formula_prop_le_lemma int_term_value_constant_lemma int_term_value_var_lemma int_formula_prop_not_lemma int_formula_prop_less_lemma int_term_value_add_lemma int_formula_prop_wf add_nat_plus nat_plus_wf nat_plus_properties add-is-int-iff intformeq_wf int_formula_prop_eq_lemma equal_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation lambdaFormation cut thin introduction extract_by_obid sqequalHypSubstitution isectElimination cumulativity hypothesisEquality hypothesis sqequalRule lambdaEquality natural_numberEquality applyEquality because_Cache independent_isectElimination setElimination rename setEquality independent_functionElimination dependent_functionElimination universeEquality isect_memberEquality voidElimination voidEquality independent_pairFormation imageElimination productElimination addLevel impliesFunctionality addEquality equalityTransitivity equalitySymmetry unionElimination applyLambdaEquality dependent_pairFormation int_eqEquality intEquality computeAll dependent_set_memberEquality pointwiseFunctionality promote_hyp baseApply closedConclusion baseClosed inlFormation inrFormation

Latex:
\mforall{}[T:Type].  \mforall{}L:bag(T)  List.  (0  <  \#(bag-union(L))  \mLeftarrow{}{}\mRightarrow{}  (\mexists{}b\mmember{}L.  0  <  \#(b)))



Date html generated: 2017_10_01-AM-08_47_04
Last ObjectModification: 2017_07_26-PM-04_31_44

Theory : bags


Home Index