#include <bits/stdc++.h>
using ll = long long;
#define rep(i, n) for (int i = 0, i##_len = (n); i < i##_len; ++i)
#define reps(i, n) for (int i = 1, i##_len = (n); i <= i##_len; ++i)
#define rrep(i, n) for (int i = ((int)(n)-1); i >= 0; --i)
#define rreps(i, n) for (int i = ((int)(n)); i > 0; --i)
#define rep2(i, s, n) for (int i = (s); i < (int)(n); i++)
#define repc2(i, s, n) for (int i = (s); i <= (int)(n); i++)
constexpr int inf = 2000'000'000;
constexpr ll linf = 4000000000000000000ll;
constexpr ll M7 = 1000000007ll;
constexpr ll M09 = 1000000009ll;
constexpr ll M9 = 998244353ll;
#define all(v) begin(v), end(v)
#define rall(v) rbegin(v), rend(v)
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n;
    cin >> n;

    vector<vector<ll>> a(n, vector<ll>(3));
    rep(i, n) rep(j, 3) cin >> a[i][j];
    using P = pair<ll, ll>;
    vector<vector<vector<P>>> dp(n + 1, vector<vector<P>>(3, vector<P>(n + 1, {-linf, -linf})));
    dp[0][0][0] = dp[0][1][0] = dp[0][2][0] = {0, 0};

    auto fmax = [&](P a, P b, int i) {
        ll t = n - 1 - i;
        auto [da, xa] = a;
        auto [db, xb] = b;
        if (da == -linf) return b;
        if (db == -linf) return a;
        if (xa == xb) return da > db ? a : b;
        ll sa = da + t * xa - (1 + t) * t / 2;
        ll sb = db + t * xb - (1 + t) * t / 2;
        return sa > sb ? a : b;
    };

    rep(i, n) {
        rep(j, 3) {
            rep(k, n + 1) {
                auto [d, x] = dp[i][j][k];
                rep(nj, 3) {
                    if (j == nj) continue;
                    ll aij = a[i][nj];
                    ll nx = max<ll>(0ll, x + aij - 1);
                    ll nk = min<ll>(n, nx);
                    ll nd = d + (x + aij);
                    dp[i + 1][nj][nk] = fmax(dp[i + 1][nj][nk], {nd, nx}, i);
                }
            }
        }
    }

    ll ans = -linf;
    rep(j, 3) {
        rep(k, n + 1) { ans = max(ans, dp[n][j][k].first); }
    }

    cout << ans << endl;
}