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#include <bits/stdc++.h>

using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int 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


constexpr LL mod = (LL) (1e9 + 7);

int n;
vector<int> repr, siz;


int fnd(int x) {
    if (repr[x] == x)
        return x;
    repr[x] = fnd(repr[x]);
    return repr[x];
}

void onion(int x, int y) {
    x = fnd(x);
    y = fnd(y);
    if (x == y)
        return;

    if (siz[x] < siz[y])
        swap(x, y);
    siz[x] += siz[y];
    repr[y] = x;
}

int convert(int x, int y) {
    return x * n + y;
}

LL fastpow(LL x, LL y) {
    LL res = 1;
    while (y > 0) {
        if (y % 2 == 1) {
            res *= x;
            res %= mod;
        }
        x *= x;
        x %= mod;
        y /= 2;
    }
    return res;
}


int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int k;
    cin >> n >> k;
    int m = n * n;
    vector<int> perm(n), pos(n);
    repr.resize(m);
    siz.resize(m);
    REP(i, m) {
        repr[i] = i;
        siz[i] = 1;
    }

    while (k--) {
        REP(i, n) {
            cin >> perm[i];
            perm[i]--;
            pos[perm[i]] = i;
        }

        REP(i, n) {
            REP(j, n) {
                if (i == j)
                    continue;
                int me = convert(i, j);
                int neigh = convert(pos[i], pos[j]);
                onion(me, neigh);
            }
        }
    }

    vector<int> invs(m);
    REP(i, n) {
        REP(j, i) {
            int x = convert(i, j);
            x = fnd(x);
            invs[x]++;
        }
    }

    LL ans = 0;
    REP(i, n) {
        FOR(j, i + 1, n - 1) {
            int x = convert(i, j);
            x = fnd(x);
            LL num = invs[x];
            LL den = siz[x];
            ans += num * fastpow(den, mod - 2) % mod;
            if (ans >= mod)
                ans -= mod;
        }
    }
    cout << ans << '\n';

    return 0;
}