subDisjsOfCard I p m collects the disjunction over I and the disjunctions over its
subsets of size m.
- subDisjsOfCard I p m = insert (⋃ i ∈ I, p i) {q : Set World | ∃ S ⊆ I, S.card = m ∧ q = ⋃ i ∈ S, p i}
Used by subDisjsOfCard_subset_supClosure, hsplit_subDisjsOfCard, subDisjsOfCard_card, exhIEII_subDisjsOfCard
Used in BarLev2021, GuerriniWehbe2025