Nuprl Lemma : distinct_iff_counts_le_one
∀s:DSet. ∀ps:|s| List.  (↑distinct{s}(ps) ⇐⇒ ∀x:|s|. ((x #∈ ps) ≤ 1))
Proof
Definitions occuring in Statement : 
count: a #∈ as, 
distinct: distinct{s}(ps), 
list: T List, 
assert: ↑b, 
le: A ≤ B, 
all: ∀x:A. B[x], 
iff: P ⇐⇒ Q, 
natural_number: $n, 
dset: DSet, 
set_car: |p|
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
dset: DSet, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
implies: P ⇒ Q, 
top: Top, 
assert: ↑b, 
ifthenelse: if b then t else f fi , 
btrue: tt, 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
prop: ℙ, 
rev_implies: P ⇐ Q, 
le: A ≤ B, 
less_than': less_than'(a;b), 
false: False, 
not: ¬A, 
true: True, 
infix_ap: x f y, 
ball: ball, 
bool: 𝔹, 
unit: Unit, 
it: ⋅, 
uiff: uiff(P;Q), 
uimplies: b supposing a, 
band: p ∧b q, 
bfalse: ff, 
exists: ∃x:A. B[x], 
or: P ∨ Q, 
sq_type: SQType(T), 
guard: {T}, 
bnot: ¬bb, 
gt: i > j, 
b2i: b2i(b), 
squash: ↓T, 
subtype_rel: A ⊆r B, 
decidable: Dec(P), 
satisfiable_int_formula: satisfiable_int_formula(fmla), 
ge: i ≥ j , 
less_than: a < b
Lemmas referenced : 
list_induction, 
set_car_wf, 
iff_wf, 
assert_wf, 
distinct_wf, 
all_wf, 
le_wf, 
count_wf, 
distinct_nil_lemma, 
istype-void, 
count_nil_lemma, 
distinct_cons_lemma, 
count_cons_lemma, 
list_wf, 
dset_wf, 
istype-false, 
true_wf, 
iff_weakening_uiff, 
set_eq_wf, 
equal_wf, 
assert_of_dset_eq, 
mem_wf, 
not_wf, 
b2i_wf, 
bnot_wf, 
assert_of_bnot, 
ball_char, 
infix_ap_wf, 
bool_wf, 
ball_wf, 
eqtt_to_assert, 
eqff_to_assert, 
bool_cases_sqequal, 
subtype_base_sq, 
bool_subtype_base, 
assert-bnot, 
bfalse_wf, 
assert_of_band, 
mem_iff_count_nzero, 
gt_wf, 
equal-wf-T-base, 
uiff_transitivity, 
iff_transitivity, 
squash_wf, 
istype-int, 
add_functionality_wrt_eq, 
subtype_rel_self, 
iff_weakening_equal, 
decidable__equal_int, 
decidable__le, 
full-omega-unsat, 
intformand_wf, 
intformnot_wf, 
intformle_wf, 
itermAdd_wf, 
itermConstant_wf, 
itermVar_wf, 
intformeq_wf, 
int_formula_prop_and_lemma, 
int_formula_prop_not_lemma, 
int_formula_prop_le_lemma, 
int_term_value_add_lemma, 
int_term_value_constant_lemma, 
int_term_value_var_lemma, 
int_formula_prop_eq_lemma, 
int_formula_prop_wf, 
non_neg_length, 
count_bounds, 
decidable__lt, 
intformless_wf, 
int_formula_prop_less_lemma, 
zero-add, 
b2i_bounds
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation_alt, 
cut, 
thin, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
setElimination, 
rename, 
because_Cache, 
hypothesis, 
sqequalRule, 
lambdaEquality_alt, 
dependent_functionElimination, 
hypothesisEquality, 
natural_numberEquality, 
universeIsType, 
independent_functionElimination, 
isect_memberEquality_alt, 
voidElimination, 
productIsType, 
functionIsType, 
inhabitedIsType, 
independent_pairFormation, 
productElimination, 
applyEquality, 
equalityIsType1, 
promote_hyp, 
addEquality, 
unionElimination, 
equalityElimination, 
independent_isectElimination, 
dependent_pairFormation_alt, 
equalityTransitivity, 
equalitySymmetry, 
instantiate, 
productEquality, 
baseClosed, 
imageElimination, 
imageMemberEquality, 
universeEquality, 
approximateComputation, 
int_eqEquality
Latex:
\mforall{}s:DSet.  \mforall{}ps:|s|  List.    (\muparrow{}distinct\{s\}(ps)  \mLeftarrow{}{}\mRightarrow{}  \mforall{}x:|s|.  ((x  \#\mmember{}  ps)  \mleq{}  1))
Date html generated:
2019_10_16-PM-01_05_28
Last ObjectModification:
2018_10_08-AM-10_19_15
Theory : list_2
Home
Index