Two sequences of periodic solutions with large and small norms, respectively, are obtained for Hamiltonian systems of the type -Jż = ξF z(t, z) + ηG z(t, z), where F is superquadratic at 2 = ∞ and G is subquadratic at z = 0.
關聯:
SIAM Journal on Mathematical Analysis, 32(3): 555-571