Nuprl Lemma : integer-nth-root-ext

∀n:ℕ+. ∀x:ℕ.  (∃r:ℕ [((r^n ≤ x) ∧ x < (r + 1)^n)])


Proof




Definitions occuring in Statement :  exp: i^n,  nat_plus: ℕ+,  nat: ℕ,  less_than: a < b,  le: A ≤ B,  all: ∀x:A. B[x],  sq_exists: ∃x:A [B[x]],  and: P ∧ Q,  add: n + m,  natural_number: $n
Definitions unfolded in proof :  member: t ∈ T,  integer-nth-root,  div_nat_induction,  natrec: natrec,  genrec: genrec,  so_apply: x[s1;s2],  decidable__equal_int,  decidable__int_equal,  uall: ∀[x:A]. B[x],  so_lambda: so_lambda(x,y,z,w.t[x; y; z; w]),  so_apply: x[s1;s2;s3;s4],  so_lambda: λ2x.t[x],  top: Top,  so_apply: x[s],  uimplies: b supposing a,  strict4: strict4(F),  and: P ∧ Q,  all: ∀x:A. B[x],  implies: P ⇒ Q,  has-value: (a)↓,  prop: ℙ,  guard: {T},  or: P ∨ Q,  squash: ↓T,  rem_bounds_1,  decidable__lt,  decidable__squash,  so_lambda: λ2x y.t[x; y],  decidable_functionality,  iff_preserves_decidability,  decidable__and,  decidable__less_than',  genrec-ap: genrec-ap
Lemmas referenced :  integer-nth-root,  lifting-strict-int_eq,  top_wf,  equal_wf,  has-value_wf_base,  base_wf,  is-exception_wf,  lifting-strict-spread,  lifting-strict-decide,  lifting-strict-less,  div_nat_induction,  decidable__equal_int,  decidable__int_equal,  rem_bounds_1,  decidable__lt,  decidable__squash,  decidable_functionality,  iff_preserves_decidability,  decidable__and,  decidable__less_than'
Rules used in proof :  introduction,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  cut,  instantiate,  extract_by_obid,  hypothesis,  sqequalRule,  thin,  sqequalHypSubstitution,  isectElimination,  baseClosed,  isect_memberEquality,  voidElimination,  voidEquality,  independent_isectElimination,  independent_pairFormation,  lambdaFormation,  callbyvalueDecide,  hypothesisEquality,  equalityTransitivity,  equalitySymmetry,  unionEquality,  unionElimination,  sqleReflexivity,  dependent_functionElimination,  independent_functionElimination,  baseApply,  closedConclusion,  decideExceptionCases,  inrFormation,  because_Cache,  imageMemberEquality,  imageElimination,  exceptionSqequal,  inlFormation,  callbyvalueApply,  applyExceptionCases

Latex:
\mforall{}n:\mBbbN{}\msupplus{}.  \mforall{}x:\mBbbN{}.    (\mexists{}r:\mBbbN{}  [((r\^{}n  \mleq{}  x)  \mwedge{}  x  <  (r  +  1)\^{}n)])



Date html generated: 2018_05_21-PM-07_50_18
Last ObjectModification: 2017_07_26-PM-05_28_05

Theory : general


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