OAI/NumberTheory/EgyptianFractions/PrimeFactorPrefix.lean
2 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.Problem337.list_product_crossingline 10Source documentation
A finite product crosses any threshold lying between its initial multiplier and its final value. No monotonicity assumptions on the factors are needed.
theorem list_product_crossing (l : List ℕ) (d : ℕ) (y : ℝ) (hdy : (d : ℝ) ≤ y) (hy : y < (d * l.prod : ℕ)) : ∃ a : List ℕ, ∃ p : ℕ, ∃ b : List ℕ, l = a ++ p :: b ∧ (d * a.prod : ℕ) ≤ y ∧ y < (d * a.prod * p : ℕ) := by … - theorem
OAI.Problem337.prime_factor_prefixline 30Source documentation
The longest sorted prime-factor prefix below a real threshold. The two prime-factor separation statements allow the smooth and rough parts of the divisor-moment argument to be estimated independently.
theorem prime_factor_prefix (n : ℕ) (y : ℝ) (hy : 1 ≤ y) (hyn : y < n) : ∃ d p : ℕ, 0 < d ∧ p.Prime ∧ d ∣ n ∧ (d : ℝ) ≤ y ∧ y < (d * p : ℕ) ∧ p ∣ n / d ∧ (∀ q : ℕ, q.Prime → q ∣ d → q ≤ p) ∧ (∀ q : ℕ, q.Prime → q ∣ n / d → p ≤ q) := by …