Nuprl Lemma : integer-sqrt-newton

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


Proof




Definitions occuring in Statement :  nat: ℕ,  less_than: a < b,  le: A ≤ B,  all: ∀x:A. B[x],  sq_exists: ∃x:A [B[x]],  and: P ∧ Q,  multiply: n * m,  add: n + m,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  nat: ℕ,  decidable: Dec(P),  or: P ∨ Q,  uall: ∀[x:A]. B[x],  uimplies: b supposing a,  sq_type: SQType(T),  implies: P ⇒ Q,  guard: {T},  and: P ∧ Q,  cand: A c∧ B,  le: A ≤ B,  less_than': less_than'(a;b),  false: False,  not: ¬A,  prop: ℙ,  less_than: a < b,  squash: ↓T,  true: True,  sq_exists: ∃x:A [B[x]],  nat_plus: ℕ+,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  uiff: uiff(P;Q),  subtype_rel: A ⊆r B,  top: Top,  subtract: n - m,  ge: i ≥ j ,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x]
Lemmas referenced :  two-mul,  add-swap,  one-mul,  mul-commutes,  mul-distributes-right,  mul-distributes,  int_formula_prop_wf,  int_formula_prop_le_lemma,  int_term_value_mul_lemma,  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,  intformle_wf,  itermMultiply_wf,  itermConstant_wf,  itermAdd_wf,  itermVar_wf,  intformless_wf,  intformnot_wf,  intformand_wf,  satisfiable-full-omega-tt,  nat_properties,  square_non_neg,  minus-zero,  minus-add,  add-commutes,  condition-implies-le,  le-add-cancel,  zero-add,  add-zero,  add-associates,  add_functionality_wrt_le,  not-equal-2,  not-lt-2,  decidable__lt,  isqrt_newton_wf,  less_than_wf,  and_wf,  le_wf,  false_wf,  nat_wf,  int_subtype_base,  subtype_base_sq,  decidable__equal_int
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  lemma_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  setElimination,  rename,  hypothesisEquality,  natural_numberEquality,  hypothesis,  unionElimination,  instantiate,  isectElimination,  cumulativity,  intEquality,  independent_isectElimination,  because_Cache,  independent_functionElimination,  introduction,  sqequalRule,  independent_pairFormation,  multiplyEquality,  equalityTransitivity,  equalitySymmetry,  addEquality,  imageMemberEquality,  baseClosed,  dependent_set_memberEquality,  productElimination,  voidElimination,  applyEquality,  lambdaEquality,  isect_memberEquality,  voidEquality,  minusEquality,  dependent_pairFormation,  int_eqEquality,  computeAll

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



Date html generated: 2019_06_20-PM-02_36_14
Last ObjectModification: 2019_06_12-PM-00_25_16

Theory : num_thy_1


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