A special issue in honor of Professor Tudor Zamfirescu

Tudor Zamfirescu, Zamfi, is eighty! Who would believe it when seeing him as curious and productive as always, choosing with the same infallible taste his problems? Because Zamfi, indeed, always liked problems, not theories– and has, of course, a theory explaining it. According to this choice, his mathematics is a wealth of beautiful and unexpected analytical, geometric, and combinatorial properties of objects that we others contemplate with ingenuous eyes. His style, imposed to his collaborators too, is a lesson of concise clarity, with no compromise– which is unusual for someone with his deep geometric intuition.