Simple parametric integral representations of the regular (finite) and singular parts of divergent Feynman amplitudes. I. General expressions

Simple expressions are obtained that describe the regular (finite) and singular parts of the divergent Feynman amplitudes of the lowest nontrivial orders of perturbation theory irrespective of the form of the matrix elements and the type of quantum-field models with polynomial and quasipolynomial interaction in $n$-dimensional space-time.