FormalConjectures/ErdosProblems/891.lean
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4 declarations, 4 contain sorry, 0 declared as axioms
Erdős Problem 891
References:
- erdosproblems.com/891
- [Po18] Pólya, Georg, Zur arithmetischen {U}ntersuchung der {P}olynome. Math. Z. (1918), 143--148.
- [Wikipedia] https://en.wikipedia.org/wiki/Dickson%27s_conjecture
- theorem
Erdos891.erdos_891Let $2=p_1 < p_2 < \cdots$ be the primes and $k\geq 2$ sorry line 42 sourceSource documentation
Let $2=p_1 < p_2 < \cdots$ be the primes and $k\geq 2$. Is it true that, for all sufficiently large $n$, there must exist an integer in $[n,n+p_1\cdots p_k)$ with $>k$ many prime factors?
depends on sorry what this means
Statement uses:
Iff,True,Nat,GE.ge,OfNat.ofNat,Filter.Eventually,Exists,And,Membership.mem,Finset,Finset.Ico,HAdd.hAdd,Finset.prod,Finset.range,Nat.nth,Nat.Prime,LT.lt,ArithmeticFunction,ArithmeticFunction.cardDistinctFactors,Filter.atTopProof 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_891 : answer(sorry) ↔ ∀ k ≥ 2, ∀ᶠ n in atTop, ∃ m ∈ Ico n (n + ∏ i ∈ range k, i.nth Nat.Prime), k < ω m := by … - theorem
Erdos891.erdos_891.variants.schinzelDocumented declaration: schinzel sorry line 53 sourceSource documentation
Schinzel deduced from Pólya's theorem [Po18] (that the sequence of $k$-smooth integers has unbounded gaps) that this is true with $p_1\cdots p_k$ replaced by $p_1\cdots p_{k-1}p_{k+1}$.
depends on sorry what this means
Statement uses:
Nat,GE.ge,OfNat.ofNat,Filter.Eventually,Exists,And,Membership.mem,Finset,Finset.Ico,HAdd.hAdd,HMul.hMul,Finset.prod,Finset.range,HSub.hSub,Nat.nth,Nat.Prime,LT.lt,ArithmeticFunction,ArithmeticFunction.cardDistinctFactors,Filter.atTopProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous36 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_891.variants.schinzel : ∀ k ≥ 2, ∀ᶠ n in atTop, ∃ m ∈ Ico n (n + (∏ i ∈ range (k - 1), i.nth Nat.Prime) * k.nth Nat.Prime), k < ω m := by … - theorem
Erdos891.erdos_891.variants.case_k_2This is unknown even for $k=2$ - that is, is it true that in every interval of $6$ (sufficiently large) consecutive integers there must exist one with at least $3$ prime factors? sorry line 64 sourceSource documentation
This is unknown even for $k=2$ - that is, is it true that in every interval of $6$ (sufficiently large) consecutive integers there must exist one with at least $3$ prime factors?
depends on sorry what this means
Statement uses:
Iff,True,Filter.Eventually,Nat,Exists,And,Membership.mem,Finset,Finset.Ico,HAdd.hAdd,OfNat.ofNat,LE.le,ArithmeticFunction,ArithmeticFunction.cardDistinctFactors,Filter.atTopProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous24 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_891.variants.case_k_2 : answer(sorry) ↔ ∀ᶠ n in atTop, ∃ m ∈ Ico n (n + 6), 3 ≤ ω m := by … - theorem
Erdos891.erdos_891.variants.weisenbergWeisenberg has observed that Dickson's conjecture implies the answer is no if we replace $p_1\cdots p_k$ with $p_1\cdots p_k-1$ sorry line 80 sourceSource documentation
Weisenberg has observed that Dickson's conjecture implies the answer is no if we replace $p_1\cdots p_k$ with $p_1\cdots p_k-1$. Indeed, let $L_k$ be the lowest common multiple of all integers at most $p_1\cdots p_k$. By Dickson's conjecture [Wikipedia], there are infinitely many $n'$ such that $\frac{L_k}{m}n'+1$ is prime for all $1\leq m < p_1\cdots p_k$. It follows that, if $n=L_kn'+1$, then all integers in $[n,n+p_1\cdots p_k-1)$ have at most $k$ prime factors.
The statement is conditional on Dickson's conjecture, formalised as
Dickson.dickson_conjecture.depends on sorry what this means
Statement uses:
Nat,GE.ge,OfNat.ofNat,Finset,Polynomial,Int,Membership.mem,And,Eq,WithBot,Polynomial.degree, BunyakovskyCondition, SchinzelCondition,Infinite,Set.ofPred,Nat.Prime,Int.natAbs,Polynomial.eval,Filter.Frequently,Finset.Icoand 9 moreProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous44 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_891.variants.weisenberg (k : ℕ) (hk : k ≥ 2) (hdickson : type_of% Dickson.dickson_conjecture) : ∃ᶠ n in atTop, ∀ m ∈ Ico n (n + (∏ i ∈ range k, i.nth Nat.Prime) - 1), ω m ≤ k := by …Mentions: Dickson.dickson_conjecture