(just got v12, haven't used it since v8) <--- my only excuse!

Trying to make a list of the centroids of the faces of a regular icosahedron. Here's my code:

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with(geom3d);

icosahedron(f,point(o,0,0,0);

a:=faces(f);

cent:=[];

printlevel:=-1; for k from 1 to 20 do point(A,a[k][1]):point(B,a[k][2]):point(C,a[k][3]);

print(coordinates(centroid(c,[A,B,C])));

cent:=[op(cent),coordinates(centroid(c,[A,B,C]))] od;
 

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