Nuprl Lemma : nequal-le-implies
∀[x,y:ℤ].  ((x + 1) ≤ y) supposing ((x ≤ y) and y ≠ x)
Proof
Definitions occuring in Statement : 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
le: A ≤ B
, 
nequal: a ≠ b ∈ T 
, 
add: n + m
, 
natural_number: $n
, 
int: ℤ
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
le: A ≤ B
, 
and: P ∧ Q
, 
nequal: a ≠ b ∈ T 
, 
all: ∀x:A. B[x]
, 
decidable: Dec(P)
, 
or: P ∨ Q
, 
iff: P 
⇐⇒ Q
, 
not: ¬A
, 
rev_implies: P 
⇐ Q
, 
implies: P 
⇒ Q
, 
false: False
, 
prop: ℙ
, 
uiff: uiff(P;Q)
, 
subtype_rel: A ⊆r B
, 
top: Top
, 
less_than': less_than'(a;b)
, 
true: True
, 
subtract: n - m
Lemmas referenced : 
decidable__le, 
false_wf, 
not-le-2, 
not-equal-2, 
add_functionality_wrt_le, 
add-swap, 
add-commutes, 
le-add-cancel, 
condition-implies-le, 
add-associates, 
minus-add, 
minus-one-mul, 
minus-one-mul-top, 
zero-add, 
le-add-cancel2, 
less_than'_wf, 
le_wf, 
nequal_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
sqequalHypSubstitution, 
productElimination, 
thin, 
hypothesis, 
lemma_by_obid, 
dependent_functionElimination, 
addEquality, 
hypothesisEquality, 
natural_numberEquality, 
unionElimination, 
independent_pairFormation, 
lambdaFormation, 
voidElimination, 
independent_functionElimination, 
independent_isectElimination, 
isectElimination, 
sqequalRule, 
applyEquality, 
lambdaEquality, 
isect_memberEquality, 
voidEquality, 
intEquality, 
because_Cache, 
minusEquality, 
independent_pairEquality, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry
Latex:
\mforall{}[x,y:\mBbbZ{}].    ((x  +  1)  \mleq{}  y)  supposing  ((x  \mleq{}  y)  and  y  \mneq{}  x)
Date html generated:
2016_05_13-PM-03_31_41
Last ObjectModification:
2015_12_26-AM-09_46_05
Theory : arithmetic
Home
Index