Python中的感染率求和序列

Question

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我在编码这件事上有困难。有人能帮帮我吗？

展开后的代码如下所示：

infection_0 = ((1 - )**0)*D[0]
infection_1 = ((1 - )**1)*D[0] + ((1 - )**0)*D[1]
infection_2 = ((1 - )**2)*D[0] + ((1 - )**1)*D[1] + D[2]
infection_3 = ((1 - )**3)*D[0] + ((1 - )**2)*D[1] + ((1 - )**1)*D[2] + D[3]
infection_4 = ((1 - )**4)*D[0] + ((1 - )**3)*D[1] + ((1 - )**2)*D[2] + ((1 - )**1)*D[3] + D[4]
...

其中D是n时的情形数，= 1/14。

提前感谢！

Answer 1

使用和

I[n] = sum([(1-)**(n-i)*D[i] for i in range(n+1)])

Answer 2

像这样吗？

def infection(iteration, y):
    base = 1-y
    res = 0
    for expo in range(iteration+1):
        idx = iteration - expo
        res += base**expo * D[idx]
    return res