Nuprl Lemma : nth_tl_nil
∀[n:ℤ]. (nth_tl(n;[]) ~ [])
Proof
Definitions occuring in Statement : 
nth_tl: nth_tl(n;as), 
nil: [], 
uall: ∀[x:A]. B[x], 
int: ℤ, 
sqequal: s ~ t
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
nth_tl: nth_tl(n;as), 
le_int: i ≤z j, 
lt_int: i <z j, 
bnot: ¬bb, 
ifthenelse: if b then t else f fi , 
bfalse: ff, 
btrue: tt, 
subtype_rel: A ⊆r B, 
uimplies: b supposing a, 
satisfiable_int_formula: satisfiable_int_formula(fmla), 
exists: ∃x:A. B[x], 
false: False, 
implies: P ⇒ Q, 
not: ¬A, 
all: ∀x:A. B[x], 
top: Top, 
and: P ∧ Q, 
prop: ℙ, 
bool: 𝔹, 
unit: Unit, 
it: ⋅, 
uiff: uiff(P;Q), 
guard: {T}
Lemmas referenced : 
le_int_wf, 
bool_wf, 
equal-wf-base, 
int_subtype_base, 
assert_wf, 
le_wf, 
lt_int_wf, 
less_than_wf, 
bnot_wf, 
satisfiable-full-omega-tt, 
intformand_wf, 
intformless_wf, 
itermConstant_wf, 
itermVar_wf, 
int_formula_prop_and_lemma, 
int_formula_prop_less_lemma, 
int_term_value_constant_lemma, 
int_term_value_var_lemma, 
int_formula_prop_wf, 
reduce_tl_nil_lemma, 
uiff_transitivity, 
eqtt_to_assert, 
assert_of_le_int, 
eqff_to_assert, 
assert_functionality_wrt_uiff, 
bnot_of_le_int, 
assert_of_lt_int, 
equal_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
intWeakElimination, 
sqequalHypSubstitution, 
thin, 
rename, 
hypothesis, 
sqequalRule, 
sqequalAxiom, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry, 
intEquality, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
natural_numberEquality, 
baseApply, 
closedConclusion, 
baseClosed, 
applyEquality, 
because_Cache, 
independent_isectElimination, 
dependent_pairFormation, 
lambdaEquality, 
int_eqEquality, 
dependent_functionElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
independent_pairFormation, 
computeAll, 
lambdaFormation, 
unionElimination, 
equalityElimination, 
independent_functionElimination, 
productElimination
Latex:
\mforall{}[n:\mBbbZ{}].  (nth\_tl(n;[])  \msim{}  [])
Date html generated:
2017_04_14-AM-09_25_07
Last ObjectModification:
2017_02_27-PM-03_59_30
Theory : list_1
Home
Index