“…By the symmetries of H n , there is a positive function K n (t, ρ) on (0, ∞) × (0, ∞) such that H n (t, p; t 0 , p 0 ) = K n (t 0 − t, dist H n (p, p 0 )) > 0 where ρ = dist H n (p, p 0 ) is the hyperbolic distance between p and p 0 . As remarked in [1], although K n can be explicitly computed, the formulas become unmanageable for large n; see [8] for more details.…”