高校数学の質問スレ Part438

https://ja.wikipedia.org/wiki/円周率の近似
を参考に

チュードノフスキーの式をPython
from mpmath import mp, fac, power, sqrt

def chudnovsky_pi(n_terms, precision=50):
"""Chudnovsky の公式"""
mp.dps = precision # 計算精度（桁数）を設定
total = 0
for k in range(n_terms):
num = (-1)**k * fac(6*k) * (13591409 + 545140134*k)
denom = fac(3*k) * (fac(k)**3) * power(640320, 3*k + 1.5)
total += num / denom
pi_value = 1 / (total * 12)
return pi_value


print(chudnovsky_pi(10))

3.1415926535897932384626433832795028841971693993751