FormalConjectures/Wikipedia/GaussCircleProblem.lean
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6 declarations, 4 contain sorry, 0 declared as axioms
Gauss circle problem
Reference: Wikipedia
Imports (1)
- abbrev
GaussCircleProblem.NLet $N(r)$ be the number of points $(m, n)$ within a circle of radius $r$, where $m$ and $n$ are both integers line 49 sourceSource documentation
Let $N(r)$ be the number of points $(m, n)$ within a circle of radius $r$, where $m$ and $n$ are both integers.
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
Real,NatProof uses:
Set.ncard,Prod,Int,Set.ofPred,GaussCircleProblem.N.match_1,Membership.mem,WithLp,OfNat.ofNat,ENNReal,Fin,Set,EuclideanSpace,Metric.closedBall,WithLp.toLp,Matrix.vecCons,Matrix.vecEmpty23 instances, coercions and auxiliary constants left out.
noncomputable abbrev N (r : ℝ) : ℕ := …
- abbrev
GaussCircleProblem.ELet $E(r)$ be the error term between the number of integral points inside the circle and the area of the circle; that is $N(r) = \pi r^2 + E(r)$ line 56 sourceSource documentation
Let $E(r)$ be the error term between the number of integral points inside the circle and the area of the circle; that is $N(r) = \pi r^2 + E(r)$.
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
RealProof uses:
HSub.hSub, GaussCircleProblem.N,HMul.hMul,Real.pi,HPow.hPow,Nat,OfNat.ofNat11 instances, coercions and auxiliary constants left out.
noncomputable abbrev E (r : ℝ) : ℝ := N r - π * r ^ 2 …
Mentions: GaussCircleProblem.N
- theorem
GaussCircleProblem.error_leGauss proved that $$ |E(r)|\leq 2\sqrt{2}\pi r, $$ for sufficiently large $r$ sorry line 68 sourceSource documentation
Gauss proved that $$ |E(r)|\leq 2\sqrt{2}\pi r, $$ for sufficiently large $r$.
[Ha59] Hardy, G. H. (1959). Ramanujan: Twelve Lectures on Subjects Suggested by His Life and Work(3rd ed.). New York: Chelsea Publishing Company. p. 67
depends on sorry what this means
Statement uses:
Filter.Eventually,Real,LE.le,abs, GaussCircleProblem.E,HMul.hMul,OfNat.ofNat,Nat,Real.sqrt,Real.pi,Filter.atTopProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous22 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem error_le : ∀ᶠ r in atTop, |E r| ≤ 2 * √2 * π * r := by …
Mentions: GaussCircleProblem.E
- theorem
GaussCircleProblem.error_not_isLittleOHardy and Laundau independently found a lower bound by showing that $$ |E(r)| \neq o\left(r^{1/2}(\log r)^{1/4}\right) $$ sorry line 78 sourceSource documentation
Hardy and Laundau independently found a lower bound by showing that $$ |E(r)| \neq o\left(r^{1/2}(\log r)^{1/4}\right) $$
depends on sorry what this means
Statement uses:
Not,Asymptotics.IsLittleO,Real,Filter.atTop, GaussCircleProblem.E,HMul.hMul,Real.sqrt,Real.logProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat,Nat9 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem error_not_isLittleO : ¬E =o[atTop] (fun r => √r * √√r.log) := by …
Mentions: GaussCircleProblem.E
- theorem
GaussCircleProblem.error_isBigOIt is conjectured that the correct bound is $$ |E(r)| = O\left(r^{1/2 + o(1)}\right) $$ [Ha59] Hardy, G sorry line 92 sourceSource documentation
It is conjectured that the correct bound is $$ |E(r)| = O\left(r^{1/2 + o(1)}\right) $$
[Ha59] Hardy, G. H. (1959). Ramanujan: Twelve Lectures on Subjects Suggested by His Life and Work(3rd ed.). New York: Chelsea Publishing Company. p. 67
See also https://arxiv.org/abs/2305.03549
depends on sorry what this means
Statement uses:
Exists,Real,Filter.Tendsto,Filter.atTop,nhds,OfNat.ofNat,Asymptotics.IsBigO, GaussCircleProblem.E,HPow.hPow,HAdd.hAdd,HDiv.hDiv,NatProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous42 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem error_isBigO : ∃ (o : ℝ → ℝ) (_ : Tendsto o atTop (𝓝 0)), E =O[atTop] fun r => r ^ (1/2 + o r) := by …Mentions: GaussCircleProblem.E
- theorem
GaussCircleProblem.exact_form_floorThe value of $N(r)$ can be expressed as $$ N(r) = 1 + 4\sum_{i=0}^{\infty}\left(\left\lfloor\frac{r^2}{4i+1}\right\rfloor - \left\lfloor\frac{r^2}{4i + 3}\right\rfloor\right). $$ sorry line 104 sourceSource documentation
The value of $N(r)$ can be expressed as $$ N(r) = 1 + 4\sum_{i=0}^{\infty}\left(\left\lfloor\frac{r^2}{4i+1}\right\rfloor - \left\lfloor\frac{r^2}{4i + 3}\right\rfloor\right). $$
depends on sorry what this means
Statement uses:
Real,LE.le,OfNat.ofNat,Eq,Int, GaussCircleProblem.N,HAdd.hAdd,HMul.hMul,tsum,Nat,HSub.hSub,Int.floor,HDiv.hDiv,HPow.hPow,SummationFilter.unconditionalProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous66 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem exact_form_floor (r : ℝ) (hr : 0 ≤ r) : N r = 1 + 4 * ∑' (i : ℕ), (⌊r ^ 2 / (4 * i + 1)⌋ - ⌊r ^ 2 / (4 * i + 3)⌋) := by …Mentions: GaussCircleProblem.N