2 papers
nlin.SI2008
An old Method of Jacobi to find Lagrangians
M. C. Nucci, P. G. L. Leach
In a recent paper by Ibragimov [N. H. Ibragimov, Invariant Lagrangians and a new method of integration of nonlinear equations, J. Math. Anal. Appl. 304 (2005) 212--235] a method wa…
nlin.SI2008
Aspects of proper differential sequences of ordinary differential equations
N. Euler, P. G. L. Leach
We define a proper differential sequence of ordinary differential equations and introduce a method to derive an alternative sequence of integrals for such a sequence. We describe s…