#include using namespace std; #define int long long #define rep(i,l,r) for(int i=(int)(l);i<(int)(r);i++) #define all(x) (x).begin(),(x).end() #define pb push_back templatebool chmax(T &a,T b){if(abool chmin(T &a,T b){if(a>b){a=b;return 1;}return 0;} typedef pair pii; typedef vector vi; typedef vector vvi; const int inf = 1LL<<60; const int mod = 1e9 + 7; const double eps = 1e-9; /*{ }*/ signed main() { int n; cin >> n; int sumeven = 0, sumodd = 1; int ans = 1; rep(i, 2, n+1){ if(i%2 == 0){ ans = i*sumodd; sumeven += ans; }else{ ans = i*sumeven; sumodd += ans; } } cout << ans << endl; return 0; }