Nuprl Lemma : sum-as-bag-accum

∀[n:ℕ]. ∀[f:ℕn ⟶ ℤ].  (Σ(f[x] | x < n) ~ bag-accum(x,y.x + y;0;[x∈bag-map(λx.f[x];upto(n))|¬b(x =z 0)]))


Proof




Definitions occuring in Statement :  bag-accum: bag-accum(v,x.f[v; x];init;bs),  bag-filter: [x∈b|p[x]],  bag-map: bag-map(f;bs),  upto: upto(n),  sum: Σ(f[x] | x < k),  int_seg: {i..j-},  nat: ℕ,  bnot: ¬bb,  eq_int: (i =z j),  uall: ∀[x:A]. B[x],  so_apply: x[s],  lambda: λx.A[x],  function: x:A ⟶ B[x],  add: n + m,  natural_number: $n,  int: ℤ,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  so_lambda: λ2x.t[x],  so_apply: x[s],  nat: ℕ,  bag-map: bag-map(f;bs),  bag-filter: [x∈b|p[x]],  bag-accum: bag-accum(v,x.f[v; x];init;bs),  all: ∀x:A. B[x],  prop: ℙ,  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2],  sq_type: SQType(T),  implies: P ⇒ Q,  guard: {T}
Lemmas referenced :  subtype_base_sq,  int_subtype_base,  sum-as-accum-filter,  int_seg_wf,  list_accum_wf,  filter_wf5,  map_wf,  upto_wf,  l_member_wf,  bnot_wf,  eq_int_wf,  nat_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  thin,  instantiate,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  because_Cache,  independent_isectElimination,  hypothesis,  sqequalRule,  hypothesisEquality,  lambdaEquality,  applyEquality,  natural_numberEquality,  setElimination,  rename,  intEquality,  lambdaFormation,  setEquality,  addEquality,  dependent_functionElimination,  equalityTransitivity,  equalitySymmetry,  independent_functionElimination,  sqequalAxiom,  functionEquality,  isect_memberEquality

Latex:
\mforall{}[n:\mBbbN{}].  \mforall{}[f:\mBbbN{}n  {}\mrightarrow{}  \mBbbZ{}].
    (\mSigma{}(f[x]  |  x  <  n)  \msim{}  bag-accum(x,y.x  +  y;0;[x\mmember{}bag-map(\mlambda{}x.f[x];upto(n))|\mneg{}\msubb{}(x  =\msubz{}  0)]))



Date html generated: 2016_05_15-PM-02_30_14
Last ObjectModification: 2015_12_27-AM-09_48_54

Theory : bags


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