We introduce a new class of effective interactions to be used within the
energy-density-functional approaches. They are based on regularized zero-range
interactions and constitute a consistent application of the effective-theory
methodology to low-energy phenomena in nuclei. They allow for defining the
order of expansion in terms of the order of derivatives acting on the
finite-range potential. Numerical calculations show a rapid convergence of the
expansion and independence of results of the regularization scale.Comment: 5 RevTex pages, 5 figures, misprints corrected, extended version, see
also http://iopscience.iop.org/0954-3899/labtalk-article/5109
