OAI/Combinatorics/ExpectationThreshold/SelectorCountingWordsTransport.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

Transport of words with a prescribed profile

Reindexing the domain of a word preserves every letter count. Consequently, the number of words with a prescribed profile depends only on the size of the domain, including when that domain is the subtype of a finite set.

  1. theorem OAI.TalagrandThreshold.wordProfile_comp_equiv line 21

    Source documentation

    A domain equivalence preserves the profile of a word.

    theorem wordProfile_comp_equiv (e : D ≃ E) (f : E → H) :
        wordProfile (f ∘ e) = wordProfile f := by
    …

    Mentions: OAI.TalagrandThreshold.wordProfile

  2. def OAI.TalagrandThreshold.wordFiberEquiv line 38

    Source documentation

    Reindexing gives an equivalence between words of the same profile.

    def wordFiberEquiv (e : D ≃ E) (n : H → ℕ) :
        ↥(wordFiber D n) ≃ ↥(wordFiber E n) := by
    …

    Mentions: OAI.TalagrandThreshold.wordFiber

  3. theorem OAI.TalagrandThreshold.wordFiber_card_eq_of_equiv line 52

    Source documentation

    Equivalent finite domains have equally many words of each profile.

    theorem wordFiber_card_eq_of_equiv (e : D ≃ E) (n : H → ℕ) :
        (wordFiber D n).card = (wordFiber E n).card := by
    …

    Mentions: OAI.TalagrandThreshold.wordFiber

  4. theorem OAI.TalagrandThreshold.wordFiber_card_eq_wordCount line 59

    Source documentation

    The word count on any finite domain agrees with the count on Fin.

    theorem wordFiber_card_eq_wordCount (D : Type*) {H : Type*}
        [Fintype D] [DecidableEq D] [Fintype H] [DecidableEq H] (n : H → ℕ) :
        (wordFiber D n).card = wordCount (Fintype.card D) n := by
    …

    Mentions: OAI.TalagrandThreshold.wordFiber, OAI.TalagrandThreshold.wordCount

  5. theorem OAI.TalagrandThreshold.wordFiber_finset_card line 66

    Source documentation

    Labels on a finite set are counted by the word count for its cardinality.

    theorem wordFiber_finset_card {α H : Type*} [DecidableEq α]
        [Fintype H] [DecidableEq H] (U : Finset α) (n : H → ℕ) :
        (wordFiber ↥U n).card = wordCount U.card n := by
    …

    Mentions: OAI.TalagrandThreshold.wordFiber, OAI.TalagrandThreshold.wordCount