The multiplicity of an affine direction `φ` in `c · divisorAffinePolynomial Dv` is `Dv φ`;
ProvedTypeDensity.count_normalizedFactors_divisorAffinePolynomialtype-density
The multiplicity of an affine direction φ in c · divisorAffinePolynomial Dv is Dv φ; in particular φ divides it iff Dv φ > 0.
Preamble
import Definitions.Def_TypeDensity_Basic import Definitions.Def_TypeDensity_Blowup_Directions import Mathlib.FieldTheory.RatFunc.Basic import Mathlib.MeasureTheory.Measure.Haar.Unique import Mathlib.NumberTheory.ArithmeticFunction.Moebius import Mathlib.NumberTheory.Padics.PadicIntegers import Mathlib.RingTheory.IntegralClosure.IntegralRestrict import Mathlib.RingTheory.MvPowerSeries.Basic import Mathlib.RingTheory.RamificationInertia.Basic import Mathlib.Topology.Algebra.Nonarchimedean.AdicTopology set_option autoImplicit false open TypeDensity open scoped Classical
Formal statement
theorem TypeDensity.count_normalizedFactors_divisorAffinePolynomial (k : Type) [Field k]
(Dv : ExceptionalDivisor k) (lc : k) (hlc : lc ≠ 0) (φ : AffineDirection k) :
Multiset.count φ.val (UniqueFactorizationMonoid.normalizedFactors
(Polynomial.C lc * divisorAffinePolynomial k Dv)) = Dv (some φ) ∧
(φ.val ∣ divisorAffinePolynomial k Dv ↔ 0 < Dv (some φ)) := by sorrySource
TypeDensity/Blowup/Directions.lean#L112-L152