Some associated curves of Frenet non-lightlike curves in E13

In this paper, we introduce the notion of the principal (binormal)-directional curve and the principal (binormal)-donor curve of the Frenet curve in the Minkowski space E13. Furthermore, we study some associated curves of a given Frenet curve to classify the general helices and the slant helices. Also, we introduce the natural representation of general helices and slant helices from the natural representation of plane curves and general helices, respectively. As an example, we give the natural representation of the closed slant helices constructed by circles.