N=30
epsilon=10**(-10)
i=0
xp=z=0.1
R=7.0
abserr=abs(z)
while i <= N and abserr >= epsilon*abs(z):
  z=xp*(2.0-R*xp)
  print i,z
  abserr=abs(z-xp)
  xp=z
  i=i+1