Nuprl Lemma : first_index_property

[T:Type]. ∀[P:T ⟶ 𝔹]. ∀[L:T List].
  (↑P[L[index-of-first in L.P[x] 1]]) ∧ (∃x∈firstn(index-of-first in L.P[x] 1;L). ↑P[x])) 
  supposing 0 < index-of-first in L.P[x]


Proof




Definitions occuring in Statement :  first_index: index-of-first in L.P[x] firstn: firstn(n;as) l_exists: (∃x∈L. P[x]) select: L[n] list: List assert: b bool: 𝔹 less_than: a < b uimplies: supposing a uall: [x:A]. B[x] so_apply: x[s] not: ¬A and: P ∧ Q function: x:A ⟶ B[x] subtract: m natural_number: $n universe: Type
Definitions unfolded in proof :  all: x:A. B[x] member: t ∈ T uall: [x:A]. B[x] so_apply: x[s] int_seg: {i..j-} uimplies: supposing a guard: {T} lelt: i ≤ j < k and: P ∧ Q decidable: Dec(P) or: P ∨ Q satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] false: False implies:  Q not: ¬A top: Top prop: less_than: a < b squash: T first_index: index-of-first in L.P[x] iff: ⇐⇒ Q cand: c∧ B so_lambda: λ2x.t[x] subtype_rel: A ⊆B ge: i ≥  rev_implies:  Q le: A ≤ B nat:
Lemmas referenced :  btrue_neq_bfalse assert_elim equal_wf and_wf not_assert_elim member-firstn l_exists_iff assert_witness bool_wf list_wf less_than_wf l_member_wf assert_wf firstn_wf l_exists_wf int_term_value_add_lemma itermAdd_wf lelt_wf nat_wf le_wf nat_properties search_wf non_neg_length int_term_value_subtract_lemma itermSubtract_wf first_index_wf subtract_wf int_seg_wf int_formula_prop_less_lemma intformless_wf decidable__lt int_formula_prop_wf int_term_value_var_lemma int_term_value_constant_lemma int_formula_prop_le_lemma int_formula_prop_not_lemma int_formula_prop_and_lemma itermVar_wf itermConstant_wf intformle_wf intformnot_wf intformand_wf satisfiable-full-omega-tt decidable__le length_wf int_seg_properties select_wf length_wf_nat search_property
Rules used in proof :  cut lemma_by_obid sqequalHypSubstitution sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity dependent_functionElimination thin isectElimination hypothesisEquality hypothesis lambdaEquality applyEquality cumulativity setElimination rename independent_isectElimination natural_numberEquality productElimination unionElimination dependent_pairFormation int_eqEquality intEquality isect_memberEquality voidElimination voidEquality sqequalRule independent_pairFormation computeAll because_Cache imageElimination equalityTransitivity equalitySymmetry setEquality addEquality introduction functionEquality universeEquality isect_memberFormation independent_pairEquality independent_functionElimination lambdaFormation dependent_set_memberEquality

Latex:
\mforall{}[T:Type].  \mforall{}[P:T  {}\mrightarrow{}  \mBbbB{}].  \mforall{}[L:T  List].
    (\muparrow{}P[L[index-of-first  x  in  L.P[x]  -  1]])  \mwedge{}  (\mneg{}(\mexists{}x\mmember{}firstn(index-of-first  x  in  L.P[x]  -  1;L).  \muparrow{}P[x])) 
    supposing  0  <  index-of-first  x  in  L.P[x]



Date html generated: 2016_05_15-PM-04_11_58
Last ObjectModification: 2016_01_16-AM-11_09_00

Theory : general


Home Index