Nuprl Lemma : even-plus-even
∀[n,m:ℤ].  ↑isEven(n + m) supposing (↑isEven(m)) ∧ (↑isEven(n))
Proof
Definitions occuring in Statement : 
isEven: isEven(n)
, 
assert: ↑b
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
and: P ∧ Q
, 
add: n + m
, 
int: ℤ
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
and: P ∧ Q
, 
same-parity: same-parity(n;m)
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
bool: 𝔹
, 
unit: Unit
, 
it: ⋅
, 
btrue: tt
, 
uiff: uiff(P;Q)
, 
ifthenelse: if b then t else f fi 
, 
bfalse: ff
, 
exists: ∃x:A. B[x]
, 
or: P ∨ Q
, 
sq_type: SQType(T)
, 
guard: {T}
, 
bnot: ¬bb
, 
assert: ↑b
, 
false: False
, 
rev_implies: P 
⇐ Q
, 
iff: P 
⇐⇒ Q
Lemmas referenced : 
eqtt_to_assert, 
eqff_to_assert, 
bool_cases_sqequal, 
subtype_base_sq, 
bool_wf, 
bool_subtype_base, 
assert_witness, 
same-parity_wf, 
istype-assert, 
isEven_wf, 
istype-int, 
iff_weakening_uiff, 
assert_wf, 
isEven-add
Rules used in proof : 
cut, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
sqequalHypSubstitution, 
productElimination, 
thin, 
because_Cache, 
inhabitedIsType, 
hypothesis, 
lambdaFormation_alt, 
unionElimination, 
equalityElimination, 
extract_by_obid, 
isectElimination, 
independent_isectElimination, 
sqequalRule, 
dependent_pairFormation_alt, 
equalityTransitivity, 
equalitySymmetry, 
equalityIstype, 
hypothesisEquality, 
promote_hyp, 
dependent_functionElimination, 
instantiate, 
cumulativity, 
independent_functionElimination, 
voidElimination, 
productIsType, 
isect_memberEquality_alt, 
isectIsTypeImplies, 
addEquality
Latex:
\mforall{}[n,m:\mBbbZ{}].    \muparrow{}isEven(n  +  m)  supposing  (\muparrow{}isEven(m))  \mwedge{}  (\muparrow{}isEven(n))
Date html generated:
2020_05_19-PM-10_01_21
Last ObjectModification:
2019_11_27-AM-11_42_44
Theory : num_thy_1
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