Nuprl Lemma : empty-bag-union

∀[T:Type]. ∀[bbs:bag(bag(T))].  ∀bs:bag(T). (bs ↓∈ bbs ⇒ (bs = {} ∈ bag(T))) supposing bag-union(bbs) = {} ∈ bag(T)


Proof




Definitions occuring in Statement :  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  universe: Type,  equal: s = t ∈ T,  bag-member: x ↓∈ bs,  bag-union: bag-union(bbs),  empty-bag: {},  bag: bag(T)
Lemmas :  bag-size_wf,  bag_wf,  nat_wf,  equal_wf,  equal-wf-base-T,  int_subtype_base,  equal-wf-T-base,  empty-bag-union,  subtype_base_sq,  bag-rep_wf,  empty-bag_wf,  list-subtype-bag,  member-bag-rep,  bag-member_wf,  squash_wf,  true_wf,  iff_weakening_equal

Latex:
\mforall{}[T:Type].  \mforall{}[bbs:bag(bag(T))].    \mforall{}bs:bag(T).  (bs  \mdownarrow{}\mmember{}  bbs  {}\mRightarrow{}  (bs  =  \{\}))  supposing  bag-union(bbs)  =  \{\}



Date html generated: 2015_07_23-AM-11_25_32
Last ObjectModification: 2015_02_04-PM-04_46_31

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