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// clang-format off
#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(auto i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<"("<<p.first<<", "<<p.second<<")";}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<"}";}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif
// clang-format on

// clang-format off
const int MOD = 1000000007;
int add(const int& a, const int& b) { return (a + b >= MOD ? a + b - MOD : a + b); }
int mul(const int& a, const int& b) { return 1LL * a * b % MOD; }
int fast_pow(int base, int exp);
// clang-format on

// Global variables
int nlength, nbase_perms, total_invs = 0;
vector<vector<int>> perms;
map<vector<int>, int> perm_to_id;
vector<int> to_study;


int count_inv(const vector<int>& perm);
void add_perm(const vector<int>& perm);
vector<int> apply_perm(const vector<int>& a, const vector<int>& b);


int
main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin >> nlength >> nbase_perms;
    vector<vector<int>> base_perms(nbase_perms, vector<int>(nlength));
    REP (i, nbase_perms) {
        for (auto& x : base_perms[ssize(perms)]) {
            cin >> x;
            --x;
        }
        add_perm(base_perms[ssize(perms)]);
    }
    nbase_perms = ssize(perms);
    base_perms.resize(nbase_perms);
    debug(base_perms);

    // Generate all permutations in a DFS manner
    while (!to_study.empty()) {
        int id = to_study.back();
        to_study.pop_back();
        REP (i, nbase_perms) add_perm(apply_perm(perms[id], base_perms[i]));
    }

    int q = fast_pow(ssize(perms), MOD - 2);
    cout << mul(total_invs, q) << "\n";
    return 0;
}


void
add_perm(const vector<int>& perm)
{
    if (perm_to_id.contains(perm)) return;
    perm_to_id[perm] = ssize(perms);
    to_study.emplace_back(ssize(perms));
    perms.emplace_back(perm);
    const int& inv_cnt = count_inv(perm);
    total_invs         = add(total_invs, inv_cnt);
    debug(perm, inv_cnt);
}

// Counts the number of permutation inversions O(n log n)
int
count_inv(const vector<int>& perm)
{
    // Allocate a segment tree
    int base = 1;
    while (base <= ssize(perm)) base <<= 1;
    vector<int> sum(base << 1);

    // Calculate the number of inversions
    int res = 0;
    for (const auto& x : perm) {
        // Add to res the number of guys > x
        {
            int l = base + x, r = base + ssize(perm);
            while ((l >> 1) != (r >> 1)) {
                if (!(l & 1)) res += sum[l + 1];
                if (r & 1) res += sum[r - 1];
                l >>= 1, r >>= 1;
            }
        }

        // Add 1 to x
        for (int v = base + x; v >= 1; v >>= 1) sum[v] += 1;
    }
    return res;
}

int
fast_pow(int base, int exp)
{
    int res = 1;
    while (exp) {
        if (exp & 1) res = mul(res, base);
        base = mul(base, base);
        exp >>= 1;
    }
    return res;
}

vector<int>
apply_perm(const vector<int>& a, const vector<int>& b)
{
    vector<int> res(nlength);
    REP (i, nlength) res[i] = b[a[i]];
    return res;
}