axiom
     G(-5,-7.69421)
     W(0.01)
     A(72) S(10)
     p+p+p+p+p+;
 
rules 3
   p= S(S/m) p+p[+p]--p+p S(S*m);
end

rules 1
  r=10;
  m= (1+tau);
  p= F;
end