摘要
In this article, the zeros of solutions of differential equation f^(k)(z)+A(z)f(z) = 0, are studied, where k 2, A(z) = B(e^z), B(ζ) = g1(1/ζ) + g2(ζ), g1 and g2 being entire functions with g2 transcendental and σ(g2) not equal to a positive integer or infinity. It is shown that any linearly independent solutions f1, f2, . . . , fk of Eq.(*) satisfy λe(f1 . . . fk) ≥ σ(g2) under the condition that fj(z) and fj(z+ 2πi) (j = 1, . . . , k) are linearly dependent.
In this article, the zeros of solutions of differential equation f^(k)(z)+A(z)f(z) = 0, are studied, where k 2, A(z) = B(e^z), B(ζ) = g1(1/ζ) + g2(ζ), g1 and g2 being entire functions with g2 transcendental and σ(g2) not equal to a positive integer or infinity. It is shown that any linearly independent solutions f1, f2, . . . , fk of Eq.(*) satisfy λe(f1 . . . fk) ≥ σ(g2) under the condition that fj(z) and fj(z+ 2πi) (j = 1, . . . , k) are linearly dependent.
基金
supported by the National Natural Foundation of China (10871076)
the Startup Foundation for Doctors of Jiangxi Normal University (2614)