Construct six spheres of the same size each touching four others:

> with(plottools):

> r:=(1/2)^(1/2):

> a:=sphere([1,0,0],r,color=red):

> b:=sphere([0,0,1],r,color=green):

> c:=sphere([0,0,-1],r,color=blue):

> d:=sphere([-1,0,0],r,color=yellow):

> e:=sphere([0,1,0],r,color=cyan):

> f:=sphere([0,-1,0],r,color=coral):

> with(plots):

Warning, the name changecoords has been redefined

> g;

> with(plottools):

> vrml(g,"c:/042/9/9-10.wrl",background_color=white);

>