Nuprl Lemma : double_sum_wf
∀[n,m:ℕ]. ∀[f:ℕn ⟶ ℕm ⟶ ℤ].  (sum(f[x;y] | x < n; y < m) ∈ ℤ)
Proof
Definitions occuring in Statement : 
double_sum: sum(f[x; y] | x < n; y < m)
, 
int_seg: {i..j-}
, 
nat: ℕ
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s1;s2]
, 
member: t ∈ T
, 
function: x:A ⟶ B[x]
, 
natural_number: $n
, 
int: ℤ
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
double_sum: sum(f[x; y] | x < n; y < m)
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s1;s2]
, 
nat: ℕ
, 
so_apply: x[s]
Lemmas referenced : 
sum_wf, 
int_seg_wf, 
nat_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
Error :isect_memberFormation_alt, 
introduction, 
cut, 
sqequalRule, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
lambdaEquality, 
applyEquality, 
natural_numberEquality, 
setElimination, 
rename, 
hypothesis, 
because_Cache, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry, 
Error :functionIsType, 
Error :universeIsType, 
intEquality, 
isect_memberEquality, 
functionEquality, 
Error :inhabitedIsType
Latex:
\mforall{}[n,m:\mBbbN{}].  \mforall{}[f:\mBbbN{}n  {}\mrightarrow{}  \mBbbN{}m  {}\mrightarrow{}  \mBbbZ{}].    (sum(f[x;y]  |  x  <  n;  y  <  m)  \mmember{}  \mBbbZ{})
Date html generated:
2019_06_20-PM-02_29_32
Last ObjectModification:
2018_09_26-PM-05_50_57
Theory : num_thy_1
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