... n and in the particular case of R induced by an injective mapping, Theorem improves Theorem To deal with the generalization of the most important and most difficult case of Theorem — that of small ... 0.80 The proofs of Theorems 1–4 are mostly combinatorial, with a somewhat surprising interference of graph theory in the proof of Theorem — see also Section 4, the Conclusion Proofs Proof of Theorem ... results in combinatorial number theory, L’Enseignement Math´matique, Geneva, 1980 e [6] V.F Lev, Restricted set addition in groups I The classical setting, Journal of the London Mathematical Society,...