Dipartimento di Matematica Pura ed Applicata, Università di Padova, via Belzoni 7, 35131 Padova, Italy ; Dipartimento di Matematica, Università di Bologna, Piazza di Porta San Donato, 5, 40127 Bologna, Italy
Abstract:
We study John, uniform and non-tangentially accessible domains in homogeneous groups of steps 2 and 3. We show that domains in groups of step 2 are non-tangentially accessible and we give an explicit condition which ensures the John property in groups of step 3.