OAI/Algebra/DepthFive/BidegreeBridge.lean

GitHub source file

8 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.Problem335.bidegreeWeight_eq_pair line 15

    Source documentation

    The paired weight is exactly the two complementary indicator weights.

    theorem bidegreeWeight_eq_pair (side : σ → Bool) (d : σ →₀ ℕ) :
        Finsupp.weight (bidegreeWeight side) d =
          (Finsupp.weight (Bidegree.weight side) d,
           Finsupp.weight (Bidegree.weight (fun x => !(side x))) d) := by
    …

    Mentions: OAI.Problem335.bidegreeWeight, OAI.Problem335.Bidegree.weight

  2. theorem OAI.Problem335.mem_bidegreeSubmodule_iff_indicator line 27
  3. theorem OAI.Problem335.bidegreeComponent_sub_eq_component line 47

    Source documentation

    On total degree n, a single degree projection already fixes the other degree.

    theorem bidegreeComponent_sub_eq_component (side : σ → Bool) (i : ℕ)
        {p : MvPolynomial σ R} {n : ℕ} (hp : p.IsHomogeneous n) :
        bidegreeComponent side i (n - i) p = Bidegree.component side i p := by
    …

    Mentions: OAI.Problem335.bidegreeComponent, OAI.Problem335.Bidegree.component

  4. theorem OAI.Problem335.bidegreeComponent_eq_component line 65
  5. theorem OAI.Problem335.component_mem_bidegreeSubmodule line 70
  6. theorem OAI.Problem335.sum_bidegreeComponents line 76
  7. theorem OAI.Problem335.bidegreeComponent_prod line 83

    Source documentation

    The product-rank expansion, expressed in the paired bidegree API.

    theorem bidegreeComponent_prod {ι : Type*} [Fintype ι] [DecidableEq ι]
        (side : σ → Bool) (p : ι → MvPolynomial σ R) (e : ι → ℕ)
        (hp : ∀ a, (p a).IsHomogeneous (e a)) (k m : ℕ)
        (hkm : k + m = ∑ a, e a) :
        bidegreeComponent side k m (∏ a, p a) =
          ∑ f ∈ Fintype.piFinset (fun a => Finset.range (e a + 1)),
            if (∑ a, f a) = k then
              ∏ a, bidegreeComponent side (f a) (e a - f a) (p a) else 0 := by
    …

    Mentions: OAI.Problem335.bidegreeComponent

  8. theorem OAI.Problem335.component_product_mem_bidegree line 100

    Source documentation

    A summand in the constrained expansion has the intended target bidegree.

    theorem component_product_mem_bidegree {ι : Type*} [Fintype ι]
        (side : σ → Bool) (p : ι → MvPolynomial σ R) (e f : ι → ℕ)
        (hp : ∀ a, (p a).IsHomogeneous (e a)) (k m : ℕ)
        (hkm : k + m = ∑ a, e a) (hf : ∑ a, f a = k) :
        (∏ a, Bidegree.component side (f a) (p a)) ∈ bidegreeSubmodule side k m := by
    …

    Mentions: OAI.Problem335.Bidegree.component, OAI.Problem335.bidegreeSubmodule