Lesson 4

from sympy import series
from sympy.abc import x

print(series((1 - (1 - 4 * x) ** .5) / (2 * x)))

1.0 + 1.0*x + 2.0*x**2 + 5.0*x**3 + 14.0*x**4 + 42.0*x**5 + O(x**6)