N, p = map(float, input().split())
N = int(N)

#2は扱いにくいから先に足しておく
ans = 1

for i in range(3, N+1):
    count = 0
    for j in range(2, i):
        if i%j == 0:
            count += 1
    ans += (1-p)**count

print(ans)