OAI/Algebra/DepthFive/IteratedDerivative.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.Problem335.iterate_pderiv_monomial line 14

    Source documentation

    Repeated partial differentiation acts by a falling factorial on each monomial.

    theorem iterate_pderiv_monomial (i : σ) (r : ℕ) (d : σ →₀ ℕ) (a : K) :
        (pderiv i)^[r] (monomial d a) =
          monomial (d - Finsupp.single i r) (a * (d i).descFactorial r) := by
    …
  2. theorem OAI.Problem335.iterate_pderiv_monomial_eq_zero line 30

    Source documentation

    Derivatives beyond a monomial's exponent vanish, in any characteristic.

    theorem iterate_pderiv_monomial_eq_zero (i : σ) (r : ℕ) (d : σ →₀ ℕ)
        (a : K) (h : d i < r) :
        (pderiv i)^[r] (monomial d a) = 0 := by
    …
  3. theorem OAI.Problem335.coeff_iterate_pderiv line 37

    Source documentation

    Coefficients of a repeated derivative are shifted coefficients times a rising factorial.

    theorem coeff_iterate_pderiv (i : σ) (r : ℕ) (p : MvPolynomial σ K)
        (m : σ →₀ ℕ) :
        ((pderiv i)^[r] p).coeff m =
          p.coeff (m + Finsupp.single i r) * (m i + 1).ascFactorial r := by
    …