#include #define EPS 1e-9 #define INF 1070000000LL #define MOD 1000000007LL #define fir first #define foreach(it,X) for(auto it=(X).begin();it!=(X).end();it++) #define numa(x,a) for(auto x: a) #define ite iterator #define mp make_pair #define rep(i,n) rep2(i,0,n) #define rep2(i,m,n) for(int i=m;i<(n);i++) #define pb push_back #define pf push_front #define sec second #define sz(x) ((int)(x).size()) #define ALL( c ) (c).begin(), (c).end() #define gcd(a,b) __gcd(a,b) #define mem(x,n) memset(x,n,sizeof(x)) #define endl "\n" using namespace std; template void deploy(std::ostream &os, const TUPLE &tuple){} template void deploy(std::ostream &os, const TUPLE &t){ os << (POS == 0 ? "" : ", ") << get(t); deploy(os, t); } template std::ostream& operator<<(std::ostream &os, std::pair &p){ os << "(" << p.first <<", " << p.second <<")";return os; } template std::ostream& operator<<(std::ostream &os, std::vector &v){ int remain = v.size(); os << "{"; for(auto e: v) os << e << (--remain == 0 ? "}" : ", "); return os; } template std::ostream& operator<<(std::ostream &os, std::set &v){ int remain = v.size(); os << "{"; for(auto e: v) os << e << (--remain == 0 ? "}" : ", "); return os; } template std::ostream& operator<<(std::ostream &os, std::map &mp){ int remain = mp.size(); os << "{"; for(auto e: mp) os << "(" << e.first << " -> " << e.second << ")" << (--remain == 0 ? "}" : ", "); return os; } #define DEBUG1(var0) { std::cerr << (#var0) << "=" << (var0) << endl; } #define DEBUG2(var0, var1) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG1(var1); } #define DEBUG3(var0, var1, var2) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG2(var1,var2); } #define DEBUG4(var0, var1, var2, var3) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG3(var1,var2,var3); } using ll = long long; inline bool f(int card, int i){ return (card & (1 << i)) != 0; } inline int calc(int card){ int ret = 0; rep(i,5){ ret += f(card, i) && f(card, i+1) && f(card, i+2) && f(card, i+3) && f(card, i+4); ret += f(card, i) && f(card, i+5) && f(card, i+10) && f(card, i+15) && f(card, i+20); } ret += f(card, 0) && f(card, 6) && f(card, 12) && f(card, 18) && f(card, 24); ret += f(card, 4) && f(card, 8) && f(card, 12) && f(card, 16) && f(card, 20); return ret; } inline long double comb(int n, int r){ if (n < r) { return 0; } double ret = 1; for (int i = 1; i <= r; i++, n--) { ret = ret * n / i; } return ret; } int sum[15][30]; long double times[30]; int main() { cin.tie(0); ios_base::sync_with_stdio(0); int N; cin >> N; for (int b = 1; b < (1<<25); b++) { if (__builtin_popcount(b) > N) { continue; } sum[calc(b)][__builtin_popcount(b)] += 1; } long double ans = 0; long double mom = 1.0 / comb(99,N); rep(j,N){ times[j] = comb(74,N-j) * mom; } rep(i,15){ rep(j,30){ if (sum[i][j]) { ans += i * sum[i][j] * times[j]; } } } //1/99CN cout << fixed << setprecision(10) << ans << endl; return 0; }