use pi.frink

digits = 100
pi = Pi.getPi[digits]
piStr = "$pi"

g = new graphics
p = new polyline
d = 0

for i=2 to digits+2
{
   x = -cos[.5 i^(1/i)] * log[i] 
   y = - sin[.5 i^(1/i)] * log[i]
   diam = .3/log[i]
   g.color[0,0,0]
   g.drawEllipseCenter[x,y,diam,diam]
   g.font["SansSerif", diam]
   g.color[.5,.5,.5]
   g.text[substrLen[piStr,d,1],x,y]
   d = d + 1
   p.addPoint[x,y]
}

g.color[0.8,0.8,.9]
g.add[p]
g.show[]
g.write["spiral4.svg",800,600]