N,p = map(float,input().split())
N = int(N)
cnt = [0] * (N+1)
for i in range(2,N+1):
    idx = i*2
    while idx <= N:
        cnt[idx] += 1
        idx += i
ans = 0
for i in range(2,N+1):
    ans += pow(1-p, cnt[i])
print(ans)