This is an archived version pinned as of the submission of my master's thesis. An up-to-date version may be found online.

Transitive multisets

module trees.transitive-multisets where
Imports 
open import foundation.universe-levels

open import trees.multisets
open import trees.submultisets

Idea

A multiset x is said to be transitive if y ⊑-𝕍 x for every y ∈-𝕍 x. That is, x is transitive if for every z ∈-𝕍 y ∈-𝕍 x we have z ∈-𝕍 y ≃ z ∈-𝕍 x.

Similarly, we say that x is weakly transitive if y ⊆-𝕍 x for every y ∈-𝕍 x. That is, x is weakly transitive if for every z ∈-𝕍 y ∈-𝕍 x we have z ∈-𝕍 y ↪ z ∈-𝕍 x.

Definition

Transitive multisets

is-transitive-𝕍 : {l : Level} → 𝕍 l → UU (lsuc l)
is-transitive-𝕍 {l} x = (y : 𝕍 l) → y ∈-𝕍 x → y ⊑-𝕍 x

Wealky transitive multisets

is-weakly-transitive-𝕍 : {l : Level} → 𝕍 l → UU (lsuc l)
is-weakly-transitive-𝕍 {l} x = (y : 𝕍 l) → y ∈-𝕍 x → y ⊆-𝕍 x