#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define fi first #define se second #define rep(i,n) for(int i = 0; i < (n); ++i) #define rrep(i,n) for(int i = 1; i <= (n); ++i) #define drep(i,n) for(int i = (n)-1; i >= 0; --i) #define gep(i,g,j) for(int i = g.head[j]; i != -1; i = g.e[i].next) #define each(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++) #define rng(a) a.begin(),a.end() #define maxs(x,y) x = max(x,y) #define mins(x,y) x = min(x,y) #define pb push_back #define sz(x) (int)(x).size() #define pcnt __builtin_popcount #define snuke srand((unsigned)clock()+(unsigned)time(NULL)); #define df(x) int x = in() using namespace std; typedef long long int ll; typedef pair P; typedef vector vi; typedef vector vvi; inline int in() { int x; scanf("%d",&x); return x;} inline void priv(vi a) { rep(i,sz(a)) printf("%d%c",a[i],i==sz(a)-1?'\n':' ');} const int MX = 1000005, INF = 1001001001; const ll LINF = 1e18; const double eps = 1e-10; int d[MX]; int main() { int n; double p; cin >> n >> p; p = 1-p; double ans = 0; for (int i = 2; i <= n; ++i) { for (int j = i*2; j <= n; j += i) d[j]++; ans += pow(p, d[i]); } printf("%.10f\n", ans); return 0; }