OAI/LinearAlgebra/CirculantHadamard/CyclotomicRemainder.lean

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8 declarations, 0 contain sorry, 0 declared as axioms

Scalar divisibility and monic remainders

The canonical remainder map for a monic root extension is linear over the coefficient ring. Consequently, divisibility by a scalar in the extension is equivalent to divisibility of every coefficient of the monic remainder.

The actual polynomial quotient AdjoinRoot f is such an extension; no additional representation hypothesis is required.

  1. theorem OAI.CirculantHadamard.CyclotomicRemainder.C_dvd_modByMonic_of_dvd_map line 28

    Source documentation

    Scalar divisibility in a monic root extension gives a constant-polynomial factor of the canonical remainder.

    theorem C_dvd_modByMonic_of_dvd_map (h : IsAdjoinRootMonic S f)
        (a : R) (F : R[X]) (hdiv : algebraMap R S a ∣ h.map F) :
        C a ∣ F %ₘ f := by
    …
  2. theorem OAI.CirculantHadamard.CyclotomicRemainder.dvd_map_of_C_dvd_modByMonic line 41

    Source documentation

    A constant factor of the canonical remainder gives scalar divisibility after passing to the monic root extension.

    theorem dvd_map_of_C_dvd_modByMonic (h : IsAdjoinRootMonic S f)
        (a : R) (F : R[X]) (hdiv : C a ∣ F %ₘ f) :
        algebraMap R S a ∣ h.map F := by
    …
  3. theorem OAI.CirculantHadamard.CyclotomicRemainder.map_dvd_iff_C_dvd_modByMonic line 52

    Source documentation

    Exact divisibility equivalence for a monic root extension.

    theorem map_dvd_iff_C_dvd_modByMonic (h : IsAdjoinRootMonic S f)
        (a : R) (F : R[X]) :
        algebraMap R S a ∣ h.map F ↔ C a ∣ F %ₘ f :=
    …
  4. theorem OAI.CirculantHadamard.CyclotomicRemainder.map_dvd_iff_dvd_coeff_modByMonic line 59

    Source documentation

    Scalar divisibility is equivalent to divisibility of every coefficient of the canonical remainder.

    theorem map_dvd_iff_dvd_coeff_modByMonic (h : IsAdjoinRootMonic S f)
        (a : R) (F : R[X]) :
        algebraMap R S a ∣ h.map F ↔ ∀ i, a ∣ (F %ₘ f).coeff i :=
    …
  5. theorem OAI.CirculantHadamard.CyclotomicRemainder.dvd_coeff_modByMonic_of_dvd_map line 65

    Source documentation

    Coefficient form of the forward divisibility bridge.

    theorem dvd_coeff_modByMonic_of_dvd_map (h : IsAdjoinRootMonic S f)
        (a : R) (F : R[X]) (hdiv : algebraMap R S a ∣ h.map F) (i : ℕ) :
        a ∣ (F %ₘ f).coeff i :=
    …
  6. theorem OAI.CirculantHadamard.CyclotomicRemainder.adjoinRoot_dvd_iff_C_dvd_modByMonic line 72

    Source documentation

    The actual quotient by a monic polynomial satisfies the constant-factor criterion, using its concrete IsAdjoinRootMonic constructor.

    theorem adjoinRoot_dvd_iff_C_dvd_modByMonic (f : R[X]) (hf : f.Monic)
        (a : R) (F : R[X]) :
        algebraMap R (AdjoinRoot f) a ∣ AdjoinRoot.mk f F ↔ C a ∣ F %ₘ f := by
    …
  7. theorem OAI.CirculantHadamard.CyclotomicRemainder.adjoinRoot_dvd_iff_dvd_coeff_modByMonic line 81

    Source documentation

    The concrete monic quotient has scalar divisibility exactly when all coefficients of the monic remainder have that scalar factor.

    theorem adjoinRoot_dvd_iff_dvd_coeff_modByMonic (f : R[X]) (hf : f.Monic)
        (a : R) (F : R[X]) :
        algebraMap R (AdjoinRoot f) a ∣ AdjoinRoot.mk f F ↔
          ∀ i, a ∣ (F %ₘ f).coeff i :=
    …
  8. theorem OAI.CirculantHadamard.CyclotomicRemainder.adjoinRoot_dvd_coeff_modByMonic line 90

    Source documentation

    Scalar divisibility in a monic quotient implies coefficientwise divisibility of the remainder.

    theorem adjoinRoot_dvd_coeff_modByMonic (f : R[X]) (hf : f.Monic)
        (a : R) (F : R[X])
        (hdiv : algebraMap R (AdjoinRoot f) a ∣ AdjoinRoot.mk f F) (i : ℕ) :
        a ∣ (F %ₘ f).coeff i :=
    …