OAI/NumberTheory/Ostmann/Tree/ComponentFactorial.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

Factorial costs of components in the arrangement graph

  1. theorem OAI.Ostmann.component_factorial_le line 15

    Source documentation

    Assigning a*m labeled positions to a blocks gives the factorial inequality used in the count of bad arrangements.

    theorem component_factorial_le (a m : ℕ) :
        (a * m).factorial ≤ m.factorial ^ a * a ^ (a * m) := by
    …
  2. theorem OAI.Ostmann.component_log_cost line 35
  3. theorem OAI.Ostmann.component_entropy_bound line 45

    Source documentation

    The sum of a-1 is exactly the number of leaves minus the number of components, so the entropy cost is controlled by this deficit.

    theorem component_entropy_bound {I : Type*} [Fintype I]
        (a : I → ℕ) (r : ℕ) (ha : ∀ i, 1 ≤ a i) (hsum : ∑ i, a i = r) :
        (∑ i, (a i : ℝ) * Real.log (a i)) ≤
          ((r : ℝ) - Fintype.card I) * (Real.log r + 1) := by
    …
  4. theorem OAI.Ostmann.component_factorial_product_bound line 63

    Source documentation

    Product of the component assignment counts, with the cost expressed through the deficit in the number of components.

    theorem component_factorial_product_bound {I : Type*} [Fintype I]
        (a : I → ℕ) (r m : ℕ) (ha : ∀ i, 1 ≤ a i) (hsum : ∑ i, a i = r) :
        (∏ i, ((a i * m).factorial : ℝ)) ≤
          (m.factorial : ℝ) ^ r *
            Real.exp ((m : ℝ) * ((r : ℝ) - Fintype.card I) * (Real.log r + 1)) := by
    …