Upgrading from:

NumericalMath`NSeries`

All the functionality of NumericalMath`NSeries` is now available in the newly created Numerical Calculus Package.

To access functionality from the new Numerical Calculus Package, load NumericalCalculus`:

Version 5.2 NumericalMath`NSeries`;
NSeries[Exp[x], {x, 0, 3}]