#include <bits/stdc++.h>
#define int long long
#define double long double
using namespace std;
typedef array<double, 4> ftp;
const int MAX = 300000;
const double CONST = 100000;
double dp[MAX][2];
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
int N, K, X;
double ans, Y, st, en, md;
ftp V;
vector<ftp> F;
cin >> N >> K;
st = 0, en = ans = N * CONST;
while (en - st > 0.00001) {
md = (st + en) / 2, F.clear(), F.push_back({0, 0, MAX, 0}), X = 0;
for (int i = 1; i <= N; i++) {
Y = CONST / i;
while (X + 1 < F.size() && F[X + 1][2] >= Y)
X++;
dp[i][0] = F[X][0] * Y + F[X][1] + CONST - md, dp[i][1] = F[X][3] + 1;
V = {-(double)i, dp[i][0], 0, dp[i][1]};
while (!F.empty()) {
V[2] = (F.back()[1] - V[1]) / (V[0] - F.back()[0]);
if (F.back()[2] > V[2])
break;
F.pop_back();
if (F.size() == X)
--X;
}
F.push_back(V);
}
ans = min(ans, dp[N][0] + md * K);
if (dp[N][1] <= K)
en = md;
else
st = md;
}
cout << fixed << setprecision(10) << (double)ans / CONST << '\n';
return 0;
}
