def f(n):
    for i in range(2, 131072 + 1):
        x = i ** n
        if x > 1000000000000:
            break
        t.append(1000000 / x)


x = int(input())

t = []
for i in range(x, 32):
    f(i)
t.sort()
print(int(sum(t)))

#t.extend([0] * (32 * 131072 - len(t)))


#x = 1
#while x < 32 * 131072:
#    for i in range(0, 32 * 131072, x * 2):
#        t[i] += t[i + x]
#    x *= 2

#print(int(t[0]))