# expo
# Fig. 54.3
# inputs: 16 1

def expApprox(x,n):
  x = x/(2**n)
  g = 2*x/(2-x)
  for i in range(n):
    g = g*(2+g)
  return g

n,x = map(float, input("n x=? ").split())
print(f"{1+expApprox(x,int(n)):.10f}")