Nuprl Lemma : integer-sqrt-ext

x:ℕ(∃r:ℕ [(((r r) ≤ x) ∧ x < (r 1) (r 1))])


Proof




Definitions occuring in Statement :  nat: less_than: a < b le: A ≤ B all: x:A. B[x] sq_exists: x:A [B[x]] and: P ∧ Q multiply: m add: m natural_number: $n
Definitions unfolded in proof :  so_lambda: λ2y.t[x; y] squash: T or: P ∨ Q prop: has-value: (a)↓ implies:  Q all: x:A. B[x] and: P ∧ Q strict4: strict4(F) uimplies: supposing a so_apply: x[s] top: Top so_lambda: λ2x.t[x] so_apply: x[s1;s2;s3;s4] so_lambda: so_lambda(x,y,z,w.t[x; y; z; w]) uall: [x:A]. B[x] stable__from_decidable sq_stable__from_stable iff_preserves_decidability any: any x sq_stable_from_decidable squash_elim decidable_functionality decidable__int_equal decidable__less_than' decidable__and decidable__squash decidable__equal_int decidable__lt rem_bounds_1 div_nat_induction integer-nth-root integer-sqrt genrec-ap: genrec-ap natrec: natrec so_apply: x[s1;s2] genrec: genrec efficient-exp-ext fastexp: i^n divide: n ÷ m subtract: m primtailrec: primtailrec(n;i;b;f) primrec: primrec(n;b;c) exp: i^n member: t ∈ T
Lemmas referenced :  lifting-strict-less lifting-strict-decide cbv_sqequal is-exception_wf istype-base has-value_wf_base lifting-strict-spread strict4-decide istype-void lifting-strict-int_eq integer-sqrt stable__from_decidable sq_stable__from_stable iff_preserves_decidability sq_stable_from_decidable squash_elim decidable_functionality decidable__int_equal decidable__less_than' decidable__and decidable__squash decidable__equal_int decidable__lt rem_bounds_1 div_nat_induction integer-nth-root efficient-exp-ext
Rules used in proof :  because_Cache Error :inlFormation_alt,  exceptionSqequal imageElimination imageMemberEquality Error :inrFormation_alt,  callbyvalueExceptionCases hypothesisEquality closedConclusion baseApply Error :universeIsType,  callbyvalueReduce callbyvalueCallbyvalue Error :lambdaFormation_alt,  independent_pairFormation independent_isectElimination voidElimination Error :isect_memberEquality_alt,  baseClosed isectElimination equalitySymmetry equalityTransitivity sqequalHypSubstitution thin sqequalRule hypothesis extract_by_obid instantiate cut sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution introduction

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_35
Last ObjectModification: 2019_06_12-PM-00_59_46

Theory : num_thy_1


Home Index