| # depths(t, i) = 1 ↔ t = Leaf, depths(t, i) = j ', i ≠ j ∨ t ≠ Leaf ⊦ |
depths(t, i) = j ', i ≠ j ∨ t ≠ Leaf ⊦ # depths(t, i) = 1, t = Leaf
⊦ depths(Leaf, i) = i '
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ # d ' = 0 +1], [CSIMPSEQ : ⊦ d ' = d0 ' ↔ d = d0])]]