Nuprl Lemma : biject-bool-nsub2
∃f:𝔹 ⟶ ℕ2. Bij(𝔹;ℕ2;f)
Proof
Definitions occuring in Statement : 
biject: Bij(A;B;f), 
int_seg: {i..j-}, 
bool: 𝔹, 
exists: ∃x:A. B[x], 
function: x:A ⟶ B[x], 
natural_number: $n
Definitions unfolded in proof : 
exists: ∃x:A. B[x], 
member: t ∈ T, 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
bool: 𝔹, 
unit: Unit, 
it: ⋅, 
btrue: tt, 
ifthenelse: if b then t else f fi , 
uall: ∀[x:A]. B[x], 
uiff: uiff(P;Q), 
and: P ∧ Q, 
uimplies: b supposing a, 
int_seg: {i..j-}, 
lelt: i ≤ j < k, 
le: A ≤ B, 
less_than': less_than'(a;b), 
false: False, 
not: ¬A, 
prop: ℙ, 
less_than: a < b, 
squash: ↓T, 
true: True, 
bfalse: ff, 
or: P ∨ Q, 
sq_type: SQType(T), 
guard: {T}, 
bnot: ¬bb, 
assert: ↑b, 
biject: Bij(A;B;f), 
inject: Inj(A;B;f), 
surject: Surj(A;B;f), 
decidable: Dec(P), 
subtype_rel: A ⊆r B
Lemmas referenced : 
eqtt_to_assert, 
false_wf, 
lelt_wf, 
eqff_to_assert, 
bool_cases_sqequal, 
subtype_base_sq, 
bool_wf, 
bool_subtype_base, 
assert-bnot, 
int_seg_wf, 
biject_wf, 
btrue_wf, 
le_antisymmetry_iff, 
bfalse_wf, 
decidable__int_equal, 
int_subtype_base, 
int_seg_properties, 
int_seg_subtype_special, 
int_seg_cases, 
less_than_transitivity1, 
less_than_irreflexivity
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
Error :dependent_pairFormation_alt, 
Error :lambdaEquality_alt, 
cut, 
hypothesisEquality, 
hypothesis, 
Error :inhabitedIsType, 
Error :lambdaFormation_alt, 
thin, 
sqequalHypSubstitution, 
unionElimination, 
equalityElimination, 
sqequalRule, 
introduction, 
extract_by_obid, 
isectElimination, 
productElimination, 
independent_isectElimination, 
Error :dependent_set_memberEquality_alt, 
natural_numberEquality, 
independent_pairFormation, 
Error :universeIsType, 
imageMemberEquality, 
baseClosed, 
equalityTransitivity, 
equalitySymmetry, 
Error :equalityIsType1, 
promote_hyp, 
dependent_functionElimination, 
instantiate, 
cumulativity, 
independent_functionElimination, 
because_Cache, 
voidElimination, 
Error :equalityIsType4, 
applyLambdaEquality, 
setElimination, 
rename, 
intEquality, 
baseApply, 
closedConclusion, 
applyEquality, 
hypothesis_subsumption
Latex:
\mexists{}f:\mBbbB{}  {}\mrightarrow{}  \mBbbN{}2.  Bij(\mBbbB{};\mBbbN{}2;f)
Date html generated:
2019_06_20-PM-00_26_43
Last ObjectModification:
2018_09_29-PM-11_14_09
Theory : fun_1
Home
Index