%!

306 396 translate
72 dup scale
0 setlinewidth

/circ{
  gsave
  1 exch div
  dup scale
  1 0 360 arc
   closepath stroke
  grestore
  } def

/M 150 def

/xd{ exch def }def
/l2{ add add add 2 mul def }def
/l3{ 3 mul sub }def

/net{
  dup M gt
   {12 {pop} repeat}
   {
   3 copy circ
   /C4 xd /B4 xd /A4 xd
   /C3 xd /B3 xd /A3 xd
   /C2 xd /B2 xd /A2 xd
   /C1 xd /B1 xd /A1 xd
   /A0 A1 A2 A3 A4 l2
   /B0 B1 B2 B3 B4 l2
   /C0 C1 C2 C3 C4 l2
   A1 B1 C1  A2 B2 C2  A4 B4 C4  A0 A3 l3 B0 B3 l3 C0 C3 l3
   A1 B1 C1  A3 B3 C3  A4 B4 C4  A0 A2 l3 B0 B2 l3 C0 C2 l3
   A2 B2 C2  A3 B3 C3  A4 B4 C4  A0 A1 l3 B0 B1 l3 C0 C1 l3
   net net net
   }
  ifelse
  } def

0 1.1547 .57735
1 -.57735 .57735
-1 -.57735 .57735
 9 copy circ circ circ
0 0 3.73205
 12 copy net
4 sub
net

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