Nuprl Lemma : sum-equal-terms
∀[n:ℕ]. ∀[a:ℕn ⟶ ℤ]. ∀[m:ℕ]. ∀[b:ℕm ⟶ ℤ].
  Σ(a[i] | i < n) = Σ(b[j] | j < m) ∈ ℤ 
  supposing permutation(ℤ;filter(λx.(¬b(x =z 0));map(λi.a[i];upto(n)));filter(λx.(¬b(x =z 0));map(λj.b[j];upto(m))))
Proof
Definitions occuring in Statement : 
permutation: permutation(T;L1;L2), 
upto: upto(n), 
sum: Σ(f[x] | x < k), 
filter: filter(P;l), 
map: map(f;as), 
int_seg: {i..j-}, 
nat: ℕ, 
bnot: ¬bb, 
eq_int: (i =z j), 
uimplies: b supposing a, 
uall: ∀[x:A]. B[x], 
so_apply: x[s], 
lambda: λx.A[x], 
function: x:A ⟶ B[x], 
natural_number: $n, 
int: ℤ, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
squash: ↓T, 
prop: ℙ, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
true: True, 
subtype_rel: A ⊆r B, 
guard: {T}, 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
rev_implies: P ⇐ Q, 
implies: P ⇒ Q, 
nat: ℕ
Lemmas referenced : 
equal_wf, 
squash_wf, 
true_wf, 
istype-universe, 
sum-l_sum, 
int_seg_wf, 
subtype_rel_self, 
iff_weakening_equal, 
l_sum_filter0, 
map_wf, 
upto_wf, 
l_sum_wf, 
l_sum_functionality_wrt_permutation, 
filter_wf5, 
bnot_wf, 
eq_int_wf, 
istype-int, 
l_member_wf, 
permutation_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
cut, 
applyEquality, 
thin, 
lambdaEquality_alt, 
sqequalHypSubstitution, 
imageElimination, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
equalityTransitivity, 
hypothesis, 
equalitySymmetry, 
universeIsType, 
instantiate, 
universeEquality, 
intEquality, 
sqequalRule, 
because_Cache, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
independent_isectElimination, 
productElimination, 
independent_functionElimination, 
setElimination, 
rename, 
setIsType, 
isect_memberEquality_alt, 
axiomEquality, 
isectIsTypeImplies, 
inhabitedIsType, 
functionIsType
Latex:
\mforall{}[n:\mBbbN{}].  \mforall{}[a:\mBbbN{}n  {}\mrightarrow{}  \mBbbZ{}].  \mforall{}[m:\mBbbN{}].  \mforall{}[b:\mBbbN{}m  {}\mrightarrow{}  \mBbbZ{}].
    \mSigma{}(a[i]  |  i  <  n)  =  \mSigma{}(b[j]  |  j  <  m)  
    supposing  permutation(\mBbbZ{};filter(\mlambda{}x.(\mneg{}\msubb{}(x  =\msubz{}  0));map(\mlambda{}i.a[i];upto(n)));
                                                filter(\mlambda{}x.(\mneg{}\msubb{}(x  =\msubz{}  0));map(\mlambda{}j.b[j];upto(m))))
 Date html generated: 
2020_05_20-AM-08_15_56
 Last ObjectModification: 
2020_01_04-PM-11_11_57
Theory : general
Home
Index