Nuprl Lemma : gcd_ex_n
∀b:ℕ. ∀a:ℤ.  (∃y:{ℤ| GCD(a;b;y)})
Proof
Definitions occuring in Statement : 
gcd_p: GCD(a;b;y), 
nat: ℕ, 
all: ∀x:A. B[x], 
sq_exists: ∃x:{A| B[x]}, 
int: ℤ
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
guard: {T}, 
int_seg: {i..j-}, 
lelt: i ≤ j < k, 
and: P ∧ Q, 
uimplies: b supposing a, 
satisfiable_int_formula: satisfiable_int_formula(fmla), 
exists: ∃x:A. B[x], 
false: False, 
implies: P ⇒ Q, 
not: ¬A, 
top: Top, 
prop: ℙ, 
decidable: Dec(P), 
or: P ∨ Q, 
subtype_rel: A ⊆r B, 
le: A ≤ B, 
less_than': less_than'(a;b), 
nat: ℕ, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
sq_exists: ∃x:{A| B[x]}, 
less_than: a < b, 
ge: i ≥ j , 
true: True, 
squash: ↓T, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q, 
nat_plus: ℕ+, 
uiff: uiff(P;Q), 
subtract: n - m
Lemmas referenced : 
gcd_p_shift, 
add_com, 
gcd_p_sym, 
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, 
not-lt-2, 
quot_rem_exists, 
gcd_p_zero, 
iff_weakening_equal, 
true_wf, 
squash_wf, 
int_term_value_add_lemma, 
itermAdd_wf, 
nat_properties, 
nat_wf, 
primrec-wf2, 
less_than_wf, 
set_wf, 
decidable__lt, 
gcd_p_wf, 
sq_exists_wf, 
guard_wf, 
all_wf, 
le_wf, 
int_formula_prop_eq_lemma, 
int_term_value_subtract_lemma, 
int_formula_prop_not_lemma, 
intformeq_wf, 
itermSubtract_wf, 
intformnot_wf, 
decidable__le, 
lelt_wf, 
false_wf, 
int_seg_subtype, 
subtract_wf, 
decidable__equal_int, 
int_seg_wf, 
int_formula_prop_wf, 
int_formula_prop_le_lemma, 
int_term_value_constant_lemma, 
int_term_value_var_lemma, 
int_formula_prop_less_lemma, 
int_formula_prop_and_lemma, 
intformle_wf, 
itermConstant_wf, 
itermVar_wf, 
intformless_wf, 
intformand_wf, 
satisfiable-full-omega-tt, 
int_seg_properties
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
cut, 
thin, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
natural_numberEquality, 
because_Cache, 
hypothesisEquality, 
hypothesis, 
setElimination, 
rename, 
productElimination, 
independent_isectElimination, 
dependent_pairFormation, 
lambdaEquality, 
int_eqEquality, 
intEquality, 
dependent_functionElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
sqequalRule, 
independent_pairFormation, 
computeAll, 
unionElimination, 
addLevel, 
applyEquality, 
equalityTransitivity, 
equalitySymmetry, 
setEquality, 
levelHypothesis, 
hypothesis_subsumption, 
dependent_set_memberEquality, 
introduction, 
addEquality, 
dependent_set_memberFormation, 
imageElimination, 
imageMemberEquality, 
baseClosed, 
universeEquality, 
independent_functionElimination, 
minusEquality, 
multiplyEquality
Latex:
\mforall{}b:\mBbbN{}.  \mforall{}a:\mBbbZ{}.    (\mexists{}y:\{\mBbbZ{}|  GCD(a;b;y)\})
Date html generated:
2016_05_14-PM-04_19_08
Last ObjectModification:
2016_01_14-PM-11_41_52
Theory : num_thy_1
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