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#include<cstdio>
#include<algorithm>
#include<utility>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<cmath>
#include<iostream>

// macros

#define FORE(c, a, b) for(int c=a; c<= int(b); ++c)
#define FORD(c, a, b) for(int c=a; c>= int(b); --c)
#define FORIT(it, cont, cont_t) for(cont_t::iterator it = cont.begin(); it != cont.end(); ++it)
#define REP(i, n) for(int i = 0; i < (n); ++i)
#define ALL(a) a.begin(), a.end() 
#define PR(n) printf("%d ", (int) (n)) 
#define PRL(n) printf("%lld ", (ll) (n)) 
#define SC(n) scanf("%d", &n);
#define SC2(n, m) scanf("%d%d", &n, &m);

#define xx first
#define yy second
#define pb push_back
#define mp make_pair
#define itr iterator

#define dbg if(0)
#define prd dbg printf

using namespace std;

typedef long long ll;
typedef long double ld;
typedef unsigned int uint;

typedef vector<int> vi;
typedef set<int> si;
typedef map<int, int> mi;
typedef pair<int, int> pi;
typedef vector<pi> vii;
typedef vector<vi> vvi;

typedef vector<vii> vvii;
typedef set<pi> spi;

const int MOD = 1000000007, NMAX = 3005;

int n, k, vis_count;
ll ans;
int perm[NMAX][NMAX];
vvii cc;
int visited[NMAX][NMAX];

ll power(ll x, int m) {
  prd("power %lld %d\n", x, m);
  if (m==0) return 1;
  if (m==1) return x;
  if (m % 2) return (x * power(x, m-1)) % MOD;
  ll y = power(x, m/2);
  return (y * y) % MOD; 
}

int main() {
  SC2(n,k);
  REP(i,k) {

    FORE(j,1,n) {
      SC(perm[i][j]);
    }
  }

  //printf("read %lu %d\n", cc.max_size(), 7);

  FORE(x,1,n) {
    FORE(y,1,n) if(x != y)
      if (!visited[x][y]) {
        int plus_count = 0, minus_count = 0, empty_run = 0;
        //vii comp;
        queue<pi> bfs;
        bfs.push(mp(x,y));
        visited[x][y] = 1;
        vis_count++;

        while(!bfs.empty()) {
          pi uv = bfs.front();
          bfs.pop();
          //comp.pb(uv);
          if (uv.xx < uv.yy)
            plus_count++;
          else
            minus_count++;
          
          if (vis_count == n * (n-1)) {
            continue;
            dbg if (bfs.size() % 1000 == 0)
              printf("%d / %d, queue: %d, cc: %d\n", vis_count, n * (n-1), (int) bfs.size(), (int) cc.size());
          }

          dbg if (empty_run)
            continue;
          empty_run = 1;

          REP(i,k) {
            pi next_uv = mp(perm[i][uv.xx], perm[i][uv.yy]);
            if (!visited[next_uv.xx][next_uv.yy]) {
              visited[next_uv.xx][next_uv.yy] = 1;
              bfs.push(next_uv);

              empty_run = 0;

              vis_count++;
              dbg if (vis_count % 1000 == 0 || vis_count > 8996000)
                printf("%d / %d, queue: %d, cc: %d\n", vis_count, n * (n-1), (int) bfs.size(), (int) cc.size());
            }
          }
        }

        //cc.pb(comp);
        ll q = power((ll) plus_count + minus_count, MOD - 2);
        ll p = (ll) plus_count * minus_count;
        p = p % MOD;
        ans += (ll) p * q;
        ans = ans % MOD;
        //printf("p %lld q %lld ans %lld\n", p, q, ans);
    }
  }

  //printf("bfs done\n");

  dbg REP(i, cc.size()) {
    REP(j, cc[i].size()) {
      printf("(%d %d) ", cc[i][j].xx, cc[i][j].yy);
    }
    printf("\n");
  }

  /*
  REP(i, cc.size()) {
    int cc_plus = 0;
    REP(j, cc[i].size()) 
      if (cc[i][j].xx < cc[i][j].yy)
        cc_plus++;

    
    ll q = power((ll) cc[i].size(), MOD - 2);
    ll p = (ll) cc_plus * (cc[i].size() - cc_plus);
    p = p % MOD;
    ans += (ll) p * q;
    ans = ans % MOD;
    //printf("p %lld q %lld ans %lld\n", p, q, ans);
  }*/

  PRL(ans);
  return 0;
}