Nuprl Lemma : mod2-cases
∀x:ℤ. (((x mod 2) = 0 ∈ ℤ) ∨ ((x mod 2) = 1 ∈ ℤ))
Proof
Definitions occuring in Statement : 
modulus: a mod n
, 
all: ∀x:A. B[x]
, 
or: P ∨ Q
, 
natural_number: $n
, 
int: ℤ
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
subtract: n - m
, 
top: Top
, 
uiff: uiff(P;Q)
, 
rev_implies: P 
⇐ Q
, 
iff: P 
⇐⇒ Q
, 
le: A ≤ B
, 
or: P ∨ Q
, 
decidable: Dec(P)
, 
subtype_rel: A ⊆r B
, 
false: False
, 
guard: {T}
, 
sq_type: SQType(T)
, 
uimplies: b supposing a
, 
implies: P 
⇒ Q
, 
not: ¬A
, 
nequal: a ≠ b ∈ T 
, 
int_nzero: ℤ-o
, 
prop: ℙ
, 
and: P ∧ Q
, 
true: True
, 
less_than': less_than'(a;b)
, 
squash: ↓T
, 
less_than: a < b
, 
nat_plus: ℕ+
, 
member: t ∈ T
, 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
Lemmas referenced : 
less-iff-le, 
or_wf, 
le_antisymmetry_iff, 
add-swap, 
le-add-cancel2, 
minus-zero, 
minus-add, 
add-commutes, 
condition-implies-le, 
le-add-cancel, 
zero-add, 
add-zero, 
add-associates, 
add_functionality_wrt_le, 
not-equal-2, 
false_wf, 
equal_wf, 
nequal_wf, 
true_wf, 
equal-wf-base, 
int_subtype_base, 
subtype_base_sq, 
modulus_wf, 
decidable__int_equal, 
less_than_wf, 
mod_bounds
Rules used in proof : 
orFunctionality, 
minusEquality, 
voidEquality, 
isect_memberEquality, 
lambdaEquality, 
addEquality, 
inrFormation, 
inlFormation, 
unionElimination, 
because_Cache, 
applyEquality, 
voidElimination, 
independent_functionElimination, 
equalitySymmetry, 
equalityTransitivity, 
independent_isectElimination, 
intEquality, 
cumulativity, 
instantiate, 
addLevel, 
productElimination, 
dependent_functionElimination, 
hypothesis, 
baseClosed, 
imageMemberEquality, 
independent_pairFormation, 
sqequalRule, 
natural_numberEquality, 
dependent_set_memberEquality, 
hypothesisEquality, 
thin, 
isectElimination, 
sqequalHypSubstitution, 
extract_by_obid, 
introduction, 
cut, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mforall{}x:\mBbbZ{}.  (((x  mod  2)  =  0)  \mvee{}  ((x  mod  2)  =  1))
Date html generated:
2020_05_19-PM-09_35_40
Last ObjectModification:
2019_12_16-PM-02_26_13
Theory : arithmetic
Home
Index