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#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using ld = long double;
using vi = vector<int>;
using vll = vector<ll>;
using vii = vector<pii>;

const int N = (1 << 11) + (1 << 10);
const int M = 3005;
int ojc[N * N + 10];
int sz[N * N + 10];
int inv_sz[N * N + 10];
bool vis[N * N + 10];

inline int idx(const int& i, const int& j) {
  return (i << 11) + (i << 10) + j;
}

inline int Find(const int& x) {
  if (ojc[x] == x)
    return x;
  return ojc[x] = Find(ojc[x]);
}

inline void Union(const int& xp, const int& yp) {
  int x = Find(xp);
  int y = Find(yp);
  if (x == y)
    return;

  if (sz[x] < sz[y]) {
    sz[y] += sz[x];
    inv_sz[y] += inv_sz[x];
    ojc[x] = y;

  } else {
    sz[x] += sz[y];
    inv_sz[x] += inv_sz[y];
    ojc[y] = x;
  }
}

ll fast_pow(ll a, ll w, const ll mod) {
  if (w == 0) {
    return 1LL;
  }
  if (w == 1) {
    return a % mod;
  }
  ll temp = fast_pow(a, w / 2, mod);
  temp *= temp;
  temp %= mod;
  if (w % 2 == 0) {
    return temp;
  }
  return (temp * a) % mod;
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie();
  int n, k;
  cin >> n >> k;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      ojc[idx(i, j)] = idx(i, j);
      sz[idx(i, j)] = 1;
      inv_sz[idx(i, j)] = (i < j) ? 0 : 1;
    }
  }

  vi perm(n);
  for (int x = 0; x < k; x++) {
    for (int j = 0; j < n; j++) {
      int a;
      cin >> a;
      a--;
      perm[j] = a;
    }

    for (int i = 0; i < n; i++) {
      int u = perm[i];
      // if (u < i) {
      //   continue;
      // }
      for (int j = 0; j < n; j++) {
        if (i == j)
          continue;

        int v = perm[j];
        Union(idx(i, j), idx(u, v));
      }
    }
    if (sz[Find(1)] == n * (n - 1)) {
      break;
    }
  }

  const ll mod = 1e9 + 7;
  ll nom = 0, den = 1;
  for (int i = 0; i < n; i++) {
    for (int j = i + 1; j < n; j++) {
      int id = idx(i, j);
      if (vis[Find(id)])
        continue;

      vis[Find(id)] = true;

      ll cur_nom = (ll)inv_sz[Find(id)] * (ll)(sz[Find(id)] - inv_sz[Find(id)]);

      ll cur_den = sz[Find(id)];

      // cout << i << ", " << j << ": " << cur_nom << " " << cur_den << "\n";
      // cout << cur_nom << " " << cur_den << "\n";

      ll g = __gcd(cur_nom, cur_den);
      cur_nom /= g;
      cur_den /= g;

      cur_nom %= mod;
      cur_den %= mod;

      nom = (nom * cur_den + den * cur_nom) % mod;

      // cur_den = fast_pow(cur_den, mod - 2, mod);
      den = (den * cur_den) % mod;

      // cout << "> " << nom << " " << den << "\n";
      // // assert(nom <= 1'000'000'000'000'000'000LL);
      // bigint big_g = gcd(nom, den);
      // nom /= big_g;
      // den /= big_g;
    }
  }

  // cout << "sum: " << nom << " " << den << "\n";
  // nom %= mod;
  // den %= mod;

  cout << (nom * fast_pow(den, mod - 2, mod)) % mod << "\n";
}