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// {{{ file: gru.cc | time: 13:40 13.03.2024
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>

#define each(...)    for (auto& __VA_ARGS__)
#define rep(i, b, e) for (int i = (b); i <= (e); i++)
#define rev(i, b, e) for (int i = (e); i >= (b); i--)
#define mp make_pair
#define mt make_tuple
#define x first
#define y second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define endl '\n'
#define tC template<class

using namespace std;

tC T> using V = vector<T>;
tC T1, class T2> using P = pair<T1,T2>;
tC T, class C=greater<T>> using PQ = priority_queue<T,V<T>,C>;
tC T> int sz(const T& a) { return (int)a.size(); }
tC T> bool amin(T& a, T b) { return b < a ? a = b, 1 : 0; }
tC T> bool amax(T& a, T b) { return b > a ? a = b, 1 : 0; }

using ll = long long;
using pii = P<int,int>;
using pll = P<ll,ll>;
using vi = V<int>;
using vl = V<ll>;
using vs = V<string>;
using vpi = V<pii>;
using vpl = V<pll>;

const int oo = 1e9 + 1;
const ll OO = ll(1e18) + 1;

auto now() { return chrono::high_resolution_clock::now().time_since_epoch().count(); }
mt19937 rnd(4488);
tC T> T rand(T lo, T hi) { return uniform_int_distribution<T>{lo,hi}(rnd); }

struct Debug {
#ifdef SPONGE
  tC T>Debug operator<<(const T& x) {
    cerr<<"\033[1;33m"<<x<<"\033[0m";
#else
  tC T>Debug operator<<(const T&) {
#endif
    return *this;
  }
} dbg;
#define $(x) #x<<'='<<(x)<<' '

void boost()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.precision(15);
  cout.setf(ios::fixed,ios::floatfield);
  cerr.precision(15);
  cerr.setf(ios::fixed,ios::floatfield);
}

namespace { void solve(); }
// }}}

int main()
{
  boost();
  //rnd.seed(now());
  int t=1;
  //cin>>t;
  rep(i,1,t){
    //cout<<"Case #"<<i<<": ";
    solve();
  }
}

namespace {

const int mod=1e9+7;
const int N=3033;

ll pot(ll a,ll b)
{
  ll c=1;
  while(b>0){
    if(b%2==1) c=a*c%mod;
    a=a*a%mod;
    b/=2;
  }
  return c;
}

ll odw(ll a)
{
  return pot(a,mod-2);
}

int n,k,pi[N][N],bylo[N][N];
vpi orbita;

void dfs(int a,int b)
{
  orbita.pb(mp(a,b));
  bylo[a][b]=1;
  rep(i,1,k) if(!bylo[pi[i][a]][pi[i][b]]) dfs(pi[i][a],pi[i][b]);
}

int tmp[N];
void zloz(int w,int i,int j)
{
  rep(x,1,n) tmp[x]=pi[j][pi[i][x]];
  rep(x,1,n) pi[w][x]=tmp[x];
}

void przelosuj()
{
  rep(t,1,100*n){
    int i=rand(1,k),j=rand(1,k);
    if(i!=j){
      if(rand(0,1)) zloz(i,i,j);
      else zloz(i,j,i);
    }
  }
  amin(k,50);
}

const int limit=500*500*500;

void solve()
{
  cin>>n>>k;
  rep(i,1,k) rep(j,1,n) cin>>pi[i][j];

  /*
  n=3000;
  k=3000;
  rep(i,1,k) rep(j,1,n) pi[i][j]=j;
  rep(i,1,k) shuffle(pi[i]+1,pi[i]+n+1,rnd);
  */
  if(ll(n)*ll(n)*k>limit) przelosuj();

  ll odp=0;
  rep(a,1,n) rep(b,1,n) if(a!=b && !bylo[a][b]){
    orbita.clear();
    dfs(a,b);
    ll zle=0,dobre=0;
    each([x,y]:orbita){
      if(x<y) dobre++; else zle++;
    }
    odp+=(zle*dobre)%mod*odw(zle+dobre)%mod;
    odp%=mod;
  }
  cout<<odp<<endl;
}

}