Nuprl Lemma : absval_lbound
∀i:ℤ. ∀n:ℕ.  (|i| > n ⇐⇒ i < -n ∨ (i > n))
Proof
Definitions occuring in Statement : 
absval: |i|, 
nat: ℕ, 
less_than: a < b, 
gt: i > j, 
all: ∀x:A. B[x], 
iff: P ⇐⇒ Q, 
or: P ∨ Q, 
minus: -n, 
int: ℤ
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
implies: P ⇒ Q, 
bool: 𝔹, 
unit: Unit, 
it: ⋅, 
btrue: tt, 
uiff: uiff(P;Q), 
and: P ∧ Q, 
uimplies: b supposing a, 
less_than: a < b, 
less_than': less_than'(a;b), 
top: Top, 
true: True, 
squash: ↓T, 
not: ¬A, 
false: False, 
prop: ℙ, 
iff: P ⇐⇒ Q, 
nat: ℕ, 
decidable: Dec(P), 
or: P ∨ Q, 
rev_implies: P ⇐ Q, 
gt: i > j, 
guard: {T}, 
subtype_rel: A ⊆r B, 
le: A ≤ B, 
bfalse: ff, 
exists: ∃x:A. B[x], 
sq_type: SQType(T), 
bnot: ¬bb, 
ifthenelse: if b then t else f fi , 
assert: ↑b, 
ge: i ≥ j , 
subtract: n - m, 
sq_stable: SqStable(P)
Lemmas referenced : 
absval_unfold2, 
lt_int_wf, 
bool_wf, 
eqtt_to_assert, 
assert_of_lt_int, 
top_wf, 
less_than_wf, 
decidable__lt, 
gt_wf, 
false_wf, 
not-lt-2, 
minus-le, 
not-gt-2, 
less-iff-le, 
add_functionality_wrt_le, 
add-associates, 
add-commutes, 
le-add-cancel, 
or_wf, 
eqff_to_assert, 
equal_wf, 
bool_cases_sqequal, 
subtype_base_sq, 
bool_subtype_base, 
iff_transitivity, 
assert_wf, 
bnot_wf, 
not_wf, 
iff_weakening_uiff, 
assert_of_bnot, 
nat_wf, 
add_functionality_wrt_lt, 
le_reflexive, 
minus-one-mul, 
add-mul-special, 
zero-mul, 
nat_properties, 
condition-implies-le, 
minus-add, 
add-swap, 
minus-one-mul-top, 
add-zero, 
minus-zero, 
zero-add, 
two-mul, 
subtract_wf, 
sq_stable_from_decidable, 
le_wf, 
decidable__le
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
sqequalRule, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
hypothesis, 
natural_numberEquality, 
unionElimination, 
equalityElimination, 
equalityTransitivity, 
equalitySymmetry, 
productElimination, 
independent_isectElimination, 
because_Cache, 
lessCases, 
isect_memberFormation, 
sqequalAxiom, 
isect_memberEquality, 
independent_pairFormation, 
voidElimination, 
voidEquality, 
imageMemberEquality, 
baseClosed, 
imageElimination, 
independent_functionElimination, 
dependent_functionElimination, 
minusEquality, 
setElimination, 
rename, 
inlFormation, 
inrFormation, 
addEquality, 
applyEquality, 
addLevel, 
orFunctionality, 
dependent_pairFormation, 
promote_hyp, 
instantiate, 
cumulativity, 
impliesFunctionality, 
intEquality, 
multiplyEquality, 
lambdaEquality
Latex:
\mforall{}i:\mBbbZ{}.  \mforall{}n:\mBbbN{}.    (|i|  >  n  \mLeftarrow{}{}\mRightarrow{}  i  <  -n  \mvee{}  (i  >  n))
Date html generated:
2017_04_14-AM-07_17_12
Last ObjectModification:
2017_02_27-PM-02_52_09
Theory : arithmetic
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