∀[P:pi_term()]. pi-rank(P) = (pi-rank(picomm-body(P)) + 1) ∈ ℕ supposing ↑picomm?(P){ Auto }1. P : pi_term()2. ↑picomm?(P)⊢ pi-rank(P) = (pi-rank(picomm-body(P)) + 1) ∈ ℕ