OAI/NumberTheory/Ostmann/Characters/FiniteKernelExclusion.lean
3 declarations, 0 contain sorry, 0 declared as axioms
Removing a finite family of exceptional signed kernel products
- theorem
OAI.Ostmann.kernel_pair_filter_mem_cardline 11 - theorem
OAI.Ostmann.kernel_pair_finite_exclusion_boundline 27 - theorem
OAI.Ostmann.exists_populated_outside_kernel_familyline 36Source documentation
The surviving kernel pair carries a large product of the actual endpoint populations, after deletion of every product in D.
theorem exists_populated_outside_kernel_family (S T : Finset ℤ) (f g : ℤ → ℤ) (D : Finset ℤ) (E K : ℝ) (hK : 0 ≤ K) (hbad : (((S.product T).filter fun z => f z.1 * g z.2 ∈ D).card : ℝ) ≤ E) (hlarge : ((S.image f).card : ℝ) * (T.image g).card * K + E < (S.card : ℝ) * T.card) : ∃ u ∈ S.image f, ∃ v ∈ T.image g, u * v ∉ D ∧ K < ((S.filter fun x => f x = u).card : ℝ) * (T.filter fun y => g y = v).card := by …