"""
Aufgabe 29
(c) Jürgen Meier
www.3d-meier.de
14.12.2025
"""

import math


k = 21    # Laufvariable
s = 0.0   # Summe 

for k in range(1, k+1):
    a = 4.0*k-1
    b = 4.0*k+3
    s = s + 3/(a*b)    
    print(s)

print("--------------------")
print(7.0/29)