In[]:=
n=20;(*Howmanyverticesdoyouwant?*)k=1;(*Towhatpowerdoyouwishtoraiseyourfunction?*)(*Iwouldn'trecommendeditingbelowthiscommentunlessyouknowwhatyou'redoing*)GraphPlot[Table[Rule@@{i+1,Mod[i+k,n]+1},{i,0,n-1}],VertexLabelsPlaced[Automatic,Center],VertexSize.5,DirectedEdgesTrue]
Out[]=
