文摘
In this paper, we prove the existence of solutions for two kinds of nonlinear fractional differential systems with coupled nonlocal initial conditions, the approach is based on the fixed point theorem of Perov and the choice of suitable norm for vectors. Further, Hyers–Ulam stability problems are discussed for these two kinds of nonlinear fractional systems. Two examples are presented to illustrate the theory. Keywords Nonlinear fractional differential equations Nonlocal initial conditions Hyers–Ulam stability Vector-valued norm