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#include <bits/stdc++.h>
using namespace std;
 
#ifdef DEBUG
auto &operator<<(auto &o, pair<auto, auto> p) {
    return o << "()" << p.first << ", " << p.second <<")";
}
auto operator<<(auto &o, auto x)-> decltype(x.end(), o) {
    o << "{";int i = 0;
    for(auto e : x) o << ", "+!i++<<e;
    return o <<"}";
}
#define debug(x...) cerr << "["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(x)
#else
#define debug(...) {}
#endif
 
#define all(x) x.begin(), x.end()
#define pb push_back
#define fi first
#define se second
typedef pair <int, int> pii;
 
constexpr long long MOD = 1e9+7;

vector <int> combine(vector <int> a, vector <int> b) {
    int n = a.size();
    vector <int> c(n);
    for (int i=1; i<n; ++i) {
        c[b[i]] = a[i];
    }
    return c;   
}


long long qpow(long long a, long long b) {
    if (b == 0) return 1;
    if (b & 1) {
        return (qpow(a, b-1)*a)%MOD;
    }
    long long x = qpow(a, b/2);
    return (x*x)%MOD;
}

void test() {
    int n; cin>>n;
    int k; cin>>k;
    vector <vector <int> > v(k, vector <int> (n+1));
    set <vector <int> > perms;
    for (int i=0; i<k; ++i) {
        for (int j=1; j<=n; ++j) {
            cin>>v[i][j];
        }
        perms.insert(v[i]);
    }


    while (true) {
        int r = perms.size();
        vector <vector <int> > toins;
        for (auto & x : perms) {
            for (int i=0; i<k; ++i) {
                toins.pb(combine(x, v[i]));
            }
        }
        for (auto x : toins) {
            perms.insert(x);
        }

        if (r == perms.size()) break;
    }
    long long res = 0;
    for (auto perm : perms) {
        debug(perm);
        for (int i=1; i<=n; i++) {
            for (int j=i+1; j<=n; ++j) {
                if (perm[i] > perm[j]) res++;
            }
        }
    }
    debug(res, perms.size(), qpow(perms.size(), MOD-2));
    cout<<(res * qpow(perms.size(), MOD-2))%MOD<<'\n';
}   
 
signed main() {
  ios_base::sync_with_stdio(0); cin.tie(0);
  int t = 1; 
  while (t--) {
    test();
  }
}