Worst-case evaluation complexity for unconstrained nonlinear
               optimization using high-order regularized models

 E. G. Birgin, J. L. Gardenghi, J. M. Martoinez, S. A. Santos; Ph. L. Toint
                  Report naXys-05-2015   June 2015

Abstract.
The worst-case evaluation complexity for smooth (possibly nonconvex)
unconstrained optimization is considered. It is shown that, if one is willing
to use derivatives of the objective function up to order p (for p >= 1)
and to assume Lipschitz continuity of the p-th derivative, then an
epsilon-approximate first-order critical point can be computed in at most
O(epsilon^{-(p+1)/p}) evaluations of the problem's objective function and
its derivatives. This generalizes and subsumes results known for p=1 and
p=2.