The Trefoil Knot

Execute the following commands in order:

The torus

c:=4
d:=1.15
torus=ParametricPlot3D[{c*Cos[t]+d*Cos[u]*Cos[t],c*Sin[t]+d*Cos[u]*Sin[t],d*Sin[u]},{t,0,2*Pi},{u,0,2Pi}]

The trefoil knot on the torus

a:=4;
b:=1.3;
Animate[
Show[torus,Graphics3D[{PointSize[0.02],Table[Point[{(a+b*Cos[3t])*Cos[2t],(a+b*Cos[3t])*Sin[2t],b*Sin[3t]}],{t,0,n,.01}]}],PlotRange->{{-5.4,5.4},{-5.4,5.4},{-1.4,1.4}}],{n,0,7}]

The trefoil knot

a:=4;
b:=1.3;
Animate[
Show[Graphics3D[{PointSize[0.02],Table[Point[{(a+b*Cos[3t])*Cos[2t],(a+b*Cos[3t])*Sin[2t],b*Sin[3t]}],{t,0,n,.01}]}],PlotRange->{{-5.4,5.4},{-5.4,5.4},{-1.4,1.4}}],{n,0,7}]