#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> VI;
typedef pair<int, int> pii;
namespace IO {
template <typename T>
inline void read(T &x) {
    x = 0;
    ll f = 1;
    char ch = getchar();
    while (!isdigit(ch)) {
        if (ch == '-')
            f = -f;
        ch = getchar();
    }
    while (isdigit(ch)) {
        x = x * 10 + ch - 48;
        ch = getchar();
    }
    x = x * f;
}
}  // namespace IO
using namespace IO;
const int maxn = 5000 + 10;
VI G[maxn];
int n;
void addedge(int x, int y) { G[x].push_back(y), G[y].push_back(x); }
ll unused[maxn][maxn << 1];
ll unused2[maxn][maxn << 1];
ll *dp[maxn];
ll *dp2[maxn];
ll siz[maxn];
int color[maxn];
const ll INF = 100000000000000ll;
void pre(int u, int fa, int c) {
    color[u] = c;
    for (int i = 0; i < G[u].size(); i++) {
        int v = G[u][i];
        if (v == fa)
            continue;
        pre(v, u, -c);
    }
}
ll ans = -INF;
void dfs(int u, int fa) {
    ans = -INF;
    siz[u] = 1;
    for (int k = -siz[u]; k <= siz[u]; k++) dp[u][k] = -INF;
    dp[u][color[u]] = 0;
    for (int i = 0; i < G[u].size(); i++) {
        int v = G[u][i];
        if (v == fa)
            continue;
        dfs(v, u);
        for (int k = -siz[u] - siz[v]; k <= siz[u] + siz[v]; k++) dp2[u][k] = -INF;
        for (int k = -siz[u]; k <= siz[u]; k++)
            for (int j = -siz[v]; j <= siz[v]; j++) dp2[u][k + j] = max(dp[u][k] + dp[v][j], dp2[u][k + j]);
        siz[u] += siz[v];
        for (int k = -siz[u]; k <= siz[u]; k++) dp[u][k] = dp2[u][k];
    }
    for (int k = -siz[u]; k <= siz[u]; k++) ans = max(ans, dp[u][k] + k * k);
    dp[u][0] = ans;
}
int main() {
    read(n);
    for (int i = 1; i <= n; i++) dp[i] = unused[i] + maxn;
    for (int i = 1; i <= n; i++) dp2[i] = unused2[i] + maxn;
    for (int i = 1; i < n; i++) {
        int x, y;
        read(x), read(y);
        addedge(x, y);
    }
    pre(1, 1, 1);
    dfs(1, 1);

    cout << ans - n;
    return 0;
}