OAI/Combinatorics/ExpectationThreshold/SelectorCountingEncodingRows.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

Counting row encodings

A row encoding chooses a subset of the available positions and labels those positions with a word of a prescribed profile. The word count depends only on the number of chosen positions, so the total count factors into a binomial coefficient and the corresponding word count.

  1. theorem OAI.TalagrandThreshold.card_fixedSize_subsets line 23

    Source documentation

    The number of subsets of R with exactly t elements.

    theorem card_fixedSize_subsets (R : Finset α) (t : ℕ) :
        Fintype.card {U : Finset α // U ⊆ R ∧ U.card = t} =
          Nat.choose R.card t := by
    …
  2. def OAI.TalagrandThreshold.RowEncoding line 34

    Source documentation

    A chosen set of positions together with labels of the prescribed profile.

    def RowEncoding (R : Finset α) (t : ℕ) (n : H → ℕ) : Type _ :=
    …
  3. instance OAI.TalagrandThreshold.instFintypeRowEncoding line 37
  4. theorem OAI.TalagrandThreshold.card_rowEncoding line 43

    Source documentation

    Each chosen set admits the same number of words, so the count factors.

    theorem card_rowEncoding (R : Finset α) (t : ℕ) (n : H → ℕ) :
        Fintype.card (RowEncoding R t n) = Nat.choose R.card t * wordCount t n := by
    …

    Mentions: OAI.TalagrandThreshold.RowEncoding, OAI.TalagrandThreshold.wordCount