FormalConjectures/ErdosProblems/321.lean
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7 declarations, 6 contain sorry, 0 declared as axioms
Erdős Problem 321
Reference: erdosproblems.com/321
Imports (1)
- def
Erdos321.RLet $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$ line 38 sourceSource documentation
Let $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$.
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
NatProof uses:
SupSet.sSup,Set.ofPred,Exists,Finset,LE.le,Finset.Icc,OfNat.ofNat,Set.InjOn,Rat,Finset.sum,HDiv.hDiv,Finset.powerset,Eq,Finset.card15 instances, coercions and auxiliary constants left out.
noncomputable def R (N : ℕ) : ℕ := …
- theorem
Erdos321.erdos_321Let $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$ sorry line 47 sourceSource documentation
Let $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$. What is $R(N)$?
depends on sorry what this means
Statement uses:
Nat,Eq, Erdos321.R,sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat2 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_321 (N : ℕ) : R N = answer(sorry) := by …Mentions: Erdos321.R
- theorem
Erdos321.erdos_321.variants.isThetaLet $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$ sorry line 65 sourceSource documentation
Let $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$. What is $\Theta(R(N))$?
depends on sorry what this means
Statement uses:
Asymptotics.IsTheta,Nat,Real,Filter.atTop, Erdos321.R,sorryAx,Bool.falseProof uses:
Lean.Name,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat9 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_321.variants.isTheta : (fun N ↦ (R N : ℝ)) =Θ[atTop] (answer(sorry) : ℕ → ℝ) := by …Mentions: Erdos321.R
- theorem
Erdos321.erdos_321.variants.isBigOLet $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$ sorry line 73 sourceSource documentation
Let $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$. Find the simplest $g(N)$ such that $R(N) = O(g(N))$.
depends on sorry what this means
Statement uses:
Asymptotics.IsBigO,Nat,Real,Filter.atTop, Erdos321.R,sorryAx,Bool.falseProof uses:
Lean.Name,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat9 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_321.variants.isBigO : (fun N ↦ (R N : ℝ)) =O[atTop] (answer(sorry) : ℕ → ℝ) := by …Mentions: Erdos321.R
- theorem
Erdos321.erdos_321.variants.isLittleOLet $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$ sorry line 81 sourceSource documentation
Let $R(N)$ be the size of the largest $A\subseteq\{1, ..., N\}$ such that all sums $\sum_{n\in S} \frac{1}{n}$ are distinct for $S\subseteq A$. Find the simplest $g(N)$ such that $R(N) = o(g(N))$.
depends on sorry what this means
Statement uses:
Asymptotics.IsLittleO,Nat,Real,Filter.atTop, Erdos321.R,sorryAx,Bool.falseProof uses:
Lean.Name,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat9 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_321.variants.isLittleO : (fun N ↦ (R N : ℝ)) =o[atTop] (answer(sorry) : ℕ → ℝ) := by …Mentions: Erdos321.R
- theorem
Erdos321.erdos_321.variants.lowerLet $R(N)$ be the maximal such size sorry line 96 sourceSource documentation
Let $R(N)$ be the maximal such size. Results of Bleicher and Erdős from [BlEr75] and [BlEr76b] imply that $$ \frac{N}{\log N} \prod_{i=3}^{k} \log_i N \le R(N), $$ valid for any $k \ge 4$ with $\log_k N \ge k$ and any $r \ge 1$ with $\log_{2r} N \ge 1$. (In these bounds $\log_i n$ denotes the $i$-fold iterated logarithm.)
[BlEr75] Bleicher, M. N. and Erdős, P., The number of distinct subsums of $\sum \sb{1}\spN\,1/i$. Math. Comp. (1975), 29-42. [BlEr76b] Bleicher, Michael N. and Erdős, Paul, Denominators of Egyptian fractions. II. Illinois J. Math. (1976), 598-613.
depends on sorry what this means
Statement uses:
Nat,LE.le,OfNat.ofNat,Real,Nat.iterate,Real.log,HMul.hMul,HDiv.hDiv,Finset.prod,Finset.Icc, Erdos321.RProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous26 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_321.variants.lower (N k : ℕ) (hk : 4 ≤ k) (hkN : k ≤ log^[k] N) : N / log N * ∏ i ∈ Finset.Icc 3 k, (log^[i] N) ≤ R N := by …Mentions: Erdos321.R
- theorem
Erdos321.erdos_321.variants.upperLet $R(N)$ be the maximal such size sorry line 115 sourceSource documentation
Let $R(N)$ be the maximal such size. Results of Bleicher and Erdős from [BlEr75] and [BlEr76b] imply that $$ R(N) \le \frac{1}{\log 2} \log_r N \left( \frac{N}{\log N} \prod_{i=3}^{r} \log_i N \right), $$ valid for any $k \ge 4$ with $\log_k N \ge k$ and any $r \ge 1$ with $\log_{2r} N \ge 1$. (In these bounds $\log_i n$ denotes the $i$-fold iterated logarithm.)
Since
Real.logis defined on all of $\mathbb{R}$, the condition $\log_{2r} N \ge 1$ is formalised as $\log_i N \ge 1$ for all $i \le 2r$, which is equivalent to it for the genuine iterated logarithm and ensures that every intermediate iterate is positive.[BlEr75] Bleicher, M. N. and Erdős, P., The number of distinct subsums of $\sum \sb{1}\spN\,1/i$. Math. Comp. (1975), 29-42. [BlEr76b] Bleicher, Michael N. and Erdős, Paul, Denominators of Egyptian fractions. II. Illinois J. Math. (1976), 598-613.
depends on sorry what this means
Statement uses:
Nat,LE.le,OfNat.ofNat,HMul.hMul,Real,Nat.iterate,Real.log, Erdos321.R,HDiv.hDiv,Finset.prod,Finset.IccProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous38 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_321.variants.upper (N r : ℕ) (hr : 1 ≤ r) (hrN : ∀ i ≤ 2 * r, 1 ≤ log^[i] N) : R N ≤ 1 / log 2 * log^[r] N * N / log N * ∏ i ∈ Finset.Icc 3 r, (log^[i] N) := by …Mentions: Erdos321.R