FormalConjectures/ErdosProblems/400.lean
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5 declarations, 3 contain sorry, 0 declared as axioms
Erdős Problem 400
Reference: erdosproblems.com/400
Imports (1)
- def
Erdos400.gFor any $k\geq 2$ let $g_k(n)$ denote the maximum value of $(a_1+\cdots+a_k)-n$ where $a_1,\ldots,a_k$ are integers such that $a_1!\cdots a_k! \mid n!$ line 37 sourceSource documentation
For any $k\geq 2$ let $g_k(n)$ denote the maximum value of $(a_1+\cdots+a_k)-n$ where $a_1,\ldots,a_k$ are integers such that $a_1!\cdots a_k! \mid n!$.
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
NatProof uses:
SupSet.sSup,Set.ofPred,Exists,Fin,Dvd.dvd,Finset.prod,Finset.univ,Nat.factorial,Eq,HSub.hSub,Finset.sum7 instances, coercions and auxiliary constants left out.
noncomputable def g (k n : ℕ) : ℕ := …
- theorem
Erdos400.erdos_400.parts.iCan one show that $\sum_{n\leq x}g_k(n) \sim c_k x\log x$ for some constant $c_k$? sorry line 44 sourceSource documentation
Can one show that $\sum_{n\leq x}g_k(n) \sim c_k x\log x$ for some constant $c_k$?
depends on sorry what this means
Statement uses:
Iff,True,Nat,GE.ge,OfNat.ofNat,Exists,Real,Asymptotics.IsEquivalent,Filter.atTop,Finset.sum,Finset.Icc, Erdos400.g,HMul.hMul,Real.logProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous28 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_400.parts.i : answer(sorry) ↔ ∀ᵉ (k ≥ 2), ∃ c : ℝ, (fun x : ℕ ↦ (∑ n ∈ Icc 1 x, (g k n : ℝ))) ~[atTop] (fun x : ℕ ↦ c * x * Real.log x) := by …Mentions: c, Erdos400.g
- theorem
Erdos400.erdos_400.parts.iiIs it true that there is a constant $c_k$ such that for almost all $n < x$ we have $g_k(n)=c_k\log x+o(\log x)$? sorry line 55 sourceSource documentation
Is it true that there is a constant $c_k$ such that for almost all $n < x$ we have $g_k(n)=c_k\log x+o(\log x)$?
depends on sorry what this means
Statement uses:
Iff,True,Nat,GE.ge,OfNat.ofNat,Exists,Real,GT.gt,Filter.Tendsto,HDiv.hDiv,Finset.card,Finset.filter,LE.le,abs,HSub.hSub, Erdos400.g,HMul.hMul,Real.log,Finset.Icc,Filter.atTopand 1 moreProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous50 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_400.parts.ii : answer(sorry) ↔ ∀ᵉ (k ≥ 2), ∃ c : ℝ, ∀ ε > 0, Tendsto (fun x : ℕ ↦ (((Icc 1 x).filter (fun n ↦ |(g k n : ℝ) - c * Real.log x| ≤ ε * Real.log x)).card : ℝ) / x) atTop (𝓝 1) := by …Mentions: c, Erdos400.g
- theorem
Erdos400.erdos_400.variants.upper_boundErdős and Graham write that it is easy to show that $g_k(n) \ll_k \log n$ always, but the best possible constant is unknown sorry line 68 sourceSource documentation
Erdős and Graham write that it is easy to show that $g_k(n) \ll_k \log n$ always, but the best possible constant is unknown.
depends on sorry what this means
Statement uses:
Nat,GE.ge,OfNat.ofNat,Asymptotics.IsBigO,Real,Filter.atTop, Erdos400.g,Real.logProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous12 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_400.variants.upper_bound (k : ℕ) (hk : k ≥ 2) : (fun n : ℕ ↦ (g k n : ℝ)) ≪ (fun n : ℕ ↦ Real.log (n : ℝ)) := by …Mentions: Erdos400.g
- theorem
Erdos400.erdos_400.variants.g_posFor $k \ge 2$, $g_k(n) > 0$ line 75 sourceSource documentation
For $k \ge 2$, $g_k(n) > 0$. We show this by choosing $a = (n, 1, 0, \ldots, 0)$.
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
Nat,GE.ge,OfNat.ofNat,LT.lt, Erdos400.gProof uses:
Eq,HAdd.hAdd,Exists,Exists.intro,HSub.hSub,Decidable.byContradiction,Not,id,Fin,ite,rfl,Finset.prod,Finset.univ,Nat.factorial,Eq.mpr,HMul.hMul,Fin.succ,congrArg,Fin.prod_univ_succ,congrFun'and 49 more63 instances, coercions and auxiliary constants left out.
Tactic trace: 23 steps
Open to load the checked before-and-after goal states.
theorem erdos_400.variants.g_pos (k n : ℕ) (h: k ≥ 2) : 0 < g k n := by …
Mentions: Erdos400.g