Nuprl Lemma : comp_nat_ind_a

∀[P:ℕ ⟶ ℙ{k}]. ((∀i:ℕ. ((∀j:ℕ. P[j] supposing j < i) ⇒ P[i])) ⇒ {∀i:ℕ. P[i]})


Proof




Definitions occuring in Statement :  nat: ℕ,  less_than: a < b,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  prop: ℙ,  guard: {T},  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  function: x:A ⟶ B[x]
Definitions unfolded in proof :  guard: {T},  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  all: ∀x:A. B[x],  member: t ∈ T,  prop: ℙ,  so_lambda: λ2x.t[x],  uimplies: b supposing a,  nat: ℕ,  so_apply: x[s],  subtype_rel: A ⊆r B,  decidable: Dec(P),  or: P ∨ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  not: ¬A,  rev_implies: P ⇐ Q,  false: False,  uiff: uiff(P;Q),  sq_stable: SqStable(P),  squash: ↓T,  subtract: n - m,  top: Top,  le: A ≤ B,  less_than': less_than'(a;b),  true: True,  nat_plus: ℕ+
Lemmas referenced :  nat_wf,  all_wf,  isect_wf,  less_than_wf,  subtype_rel_self,  decidable__le,  false_wf,  not-le-2,  sq_stable__le,  condition-implies-le,  minus-add,  minus-one-mul,  zero-add,  minus-one-mul-top,  add-associates,  add-swap,  add-commutes,  add_functionality_wrt_le,  add-zero,  le-add-cancel,  le_wf,  decidable__lt,  not-lt-2,  add-mul-special,  zero-mul,  nat_ind_a,  subtract_wf,  nat_plus_wf,  less_than_transitivity1,  less_than_irreflexivity,  less-iff-le,  minus-minus,  member-less_than
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  Error :isect_memberFormation_alt,  lambdaFormation,  cut,  introduction,  extract_by_obid,  hypothesis,  thin,  instantiate,  sqequalHypSubstitution,  isectElimination,  cumulativity,  lambdaEquality,  functionEquality,  setElimination,  rename,  hypothesisEquality,  applyEquality,  universeEquality,  because_Cache,  Error :functionIsType,  Error :universeIsType,  dependent_functionElimination,  dependent_set_memberEquality,  addEquality,  natural_numberEquality,  unionElimination,  independent_pairFormation,  voidElimination,  productElimination,  independent_functionElimination,  independent_isectElimination,  imageMemberEquality,  baseClosed,  imageElimination,  isect_memberEquality,  voidEquality,  intEquality,  minusEquality,  multiplyEquality

Latex:
\mforall{}[P:\mBbbN{}  {}\mrightarrow{}  \mBbbP{}\{k\}].  ((\mforall{}i:\mBbbN{}.  ((\mforall{}j:\mBbbN{}.  P[j]  supposing  j  <  i)  {}\mRightarrow{}  P[i]))  {}\mRightarrow{}  \{\mforall{}i:\mBbbN{}.  P[i]\})



Date html generated: 2019_06_20-AM-11_28_00
Last ObjectModification: 2018_09_26-AM-10_58_11

Theory : call!by!value_2


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