Nuprl Lemma : firstn_nth_tl_decomp
∀[T:Type]. ∀[L:T List]. ∀[i:ℕ||L||].  (L ~ firstn(i;L) @ [L[i]] @ nth_tl(1 + i;L))
Proof
Definitions occuring in Statement : 
firstn: firstn(n;as)
, 
select: L[n]
, 
length: ||as||
, 
nth_tl: nth_tl(n;as)
, 
append: as @ bs
, 
cons: [a / b]
, 
nil: []
, 
list: T List
, 
int_seg: {i..j-}
, 
uall: ∀[x:A]. B[x]
, 
add: n + m
, 
natural_number: $n
, 
universe: Type
, 
sqequal: s ~ t
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
append: as @ bs
, 
all: ∀x:A. B[x]
, 
so_lambda: so_lambda(x,y,z.t[x; y; z])
, 
top: Top
, 
so_apply: x[s1;s2;s3]
, 
subtype_rel: A ⊆r B
, 
uimplies: b supposing a
, 
le: A ≤ B
, 
and: P ∧ Q
, 
less_than': less_than'(a;b)
, 
false: False
, 
not: ¬A
, 
implies: P 
⇒ Q
, 
prop: ℙ
, 
int_seg: {i..j-}
, 
lelt: i ≤ j < k
, 
decidable: Dec(P)
, 
or: P ∨ Q
, 
less_than: a < b
, 
squash: ↓T
, 
satisfiable_int_formula: satisfiable_int_formula(fmla)
, 
exists: ∃x:A. B[x]
Lemmas referenced : 
list_wf, 
int_seg_wf, 
lelt_wf, 
int_formula_prop_wf, 
int_term_value_constant_lemma, 
int_term_value_add_lemma, 
int_term_value_var_lemma, 
int_formula_prop_less_lemma, 
int_formula_prop_not_lemma, 
int_formula_prop_and_lemma, 
itermConstant_wf, 
itermAdd_wf, 
itermVar_wf, 
intformless_wf, 
intformnot_wf, 
intformand_wf, 
satisfiable-full-omega-tt, 
decidable__lt, 
top_wf, 
subtype_rel_list, 
append_firstn_lastn_sq, 
int_seg_properties, 
false_wf, 
length_wf, 
int_seg_subtype_nat, 
nth_tl_decomp, 
list_ind_nil_lemma, 
list_ind_cons_lemma
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
sqequalRule, 
lemma_by_obid, 
sqequalHypSubstitution, 
dependent_functionElimination, 
thin, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
hypothesis, 
isectElimination, 
hypothesisEquality, 
applyEquality, 
natural_numberEquality, 
independent_isectElimination, 
independent_pairFormation, 
lambdaFormation, 
setElimination, 
rename, 
productElimination, 
lambdaEquality, 
because_Cache, 
dependent_set_memberEquality, 
addEquality, 
unionElimination, 
imageElimination, 
dependent_pairFormation, 
int_eqEquality, 
intEquality, 
computeAll, 
cumulativity, 
sqequalAxiom, 
universeEquality
Latex:
\mforall{}[T:Type].  \mforall{}[L:T  List].  \mforall{}[i:\mBbbN{}||L||].    (L  \msim{}  firstn(i;L)  @  [L[i]]  @  nth\_tl(1  +  i;L))
Date html generated:
2016_05_14-PM-02_07_57
Last ObjectModification:
2016_01_15-AM-08_03_15
Theory : list_1
Home
Index