RiemannZeta3_original.py

# Calculates Riemann's Zeta(3)
# which is also Apery's constant
# using original slow 1+1/2^3+1/3^3+...
# Juhani Kaukoranta 24.6.2018

from decimal import *
import math
import time


def Zeta3(precision):
    getcontext().prec=precision
    r = Decimal(0)
    for n in range(1,10000*precision):
        r = r+Decimal(1)/(n*n*n)
    return(r)
precision = int(input("How many numbers precision, f.eq 100 "))
time0 = time.clock()
print("Apery constant , Zeta(3) = ",Zeta3(precision))
time1 = time.clock()
print("calculation time ",time1-time0," seconds")