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: supposing a uall: [x:A]. B[x] all: x:A. B[x] implies:  Q universe: Type equal: 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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