def main(x):
    res = 0
    n = len(x)

    for i in range(1, n + 1):
        x2 = ceil(i / 2) - 1
        xn = n - i

        res += 63 * (x[x2] ** 3 - x[xn] ** 2 - 67 * x[xn]) ** 4

    return res