Kaup–Kupershmidt equation

The Kaup–Kupershmidt equation (named after David J. Kaup and Boris Abram Kupershmidt) is the nonlinear fifth-order partial differential equation The Kaup–Kupershmidt equation (named after David J. Kaup and Boris Abram Kupershmidt) is the nonlinear fifth-order partial differential equation It is the first equation in a hierarchy of integrable equations with the Lax operator It has properties similar (but not identical) to those of the better-known KdV hierarchy in which the Lax operator has order 2.