#include<bits/stdc++.h>
#include<unordered_set>
#include<unordered_map>
using namespace std;
#define REP(i,m,n) for(int i=(m);i<(n);i++)
#define rep(i,n) REP(i,0,n)
#define pb push_back
#define all(a) a.begin(),a.end()
#define rall(c) (c).rbegin(),(c).rend()
#define mp make_pair
#define double long double
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
const ll inf=1e9+7;
const ll mod=1e9+7;
int main(){
    ll n;cin>>n;
    double p;cin>>p;
    vector<double>dp(n+1);
    REP(i,2,n+1){
        ll j=i*2;
        while(j<=n){
            dp[j]+=p*(1.0-dp[j]);
            j+=i;
        }
    }
    double ans=0.0;
    REP(i,2,n+1){
        //cout<<i<<' '<<dp[i]<<endl;
        ans+=1.0-dp[i];
    }
    cout<<fixed<<setprecision(10)<<ans<<endl;
}