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#include<bits/stdc++.h>
using namespace std;
typedef long double ld;
typedef long long ll;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
const ll MOD=1e9+7;
const int LIM=3e3+7;
ll T[LIM][LIM], F[LIM*LIM], ile[LIM*LIM], inv[LIM*LIM];
ll pot(ll a, ll b) {
  ll ans=1;
  while(b) {
    if(b&1) ans=(ans*a)%MOD;
    a=(a*a)%MOD;
    b/=2;
  }
  return ans;
}
int fnd(int x) {
  if(F[x]==x) return x;
  return F[x]=fnd(F[x]);
}
void uni(int a, int b) {
  if(fnd(a)==fnd(b)) return;
  ile[fnd(a)]+=ile[fnd(b)];
  inv[fnd(a)]+=inv[fnd(b)];
  F[fnd(b)]=fnd(a);
}
int main() {
  ios_base::sync_with_stdio(0); cin.tie(0);
  int n, k;
  cin >> n >> k;
  rep(i, k) {
    rep(j, n) {
      cin >> T[i][j]; --T[i][j];
    }
  }
  rep(i, n*n) {
    F[i]=i;
    ile[i]=1;
  }
  rep(a, n) rep(b, n) if(a>b) inv[a*n+b]=1;
  rep(i, k) {
    rep(b, n) rep(a, n) uni(a*n+b, T[i][a]*n+T[i][b]);
  }
  ll ans=0;
  rep(a, n) rep(b, n) if(a<b) ans=(ans+inv[fnd(a*n+b)]*pot(ile[fnd(a*n+b)], MOD-2))%MOD;
  cout << ans << '\n';
}