Unicity theorems for meromorphic functions sharing four small functions

Abstract

Let / and g be transcendental meromorphic functions in the complex plane having properties N(r, f) < uT(r, f) + S(r, f) and N(r, g) < vT(r, g) + S(r, g) for some constants u and v satisfying (u,v) e [0,1/19) x [0,1/19). If there exist four distinct small meromorphic functions shared by / and g, then f = g.