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#include <bits/stdc++.h>
using namespace std;

constexpr int P = 1000000007;

int inv(int a)
{
	int x = 1, y = 0, q = P;
    int pos = 0;
    while (a > 0) {
        int r = q % a;
        q = q/a;
        int h = q*x + y;
        y = x;
        x = h;
        q = a;
        a = r;
        pos = !pos;
    }
    return pos ? y : (P - y);
}

int n;

using Perm = array<int, 3 * 1024>;
vector<Perm> perms;
vector<Perm> visited;

using Pair = pair<int, int>;

void Read()
{
	int k;
	scanf("%d%d", &n, &k);
	perms.resize(k);
	for (int i = 0; i < k; i++)
		for (int j = 0; j < n; j++)
		{
			int a;
			scanf("%d", &a);
			perms[i][j] = a - 1;
		}
}

vector<Pair> component;

void DFS(int a, int b)
{
	component.emplace_back(a, b);
	visited[a][b] = 1;
	for (Perm& p : perms)
	{
		int i = p[a], j = p[b];
		if (!visited[i][j])
			DFS(i, j);
	}
}

int Visit(int a, int b)
{
	DFS(a, b);
	int count = 0;
	for (auto [i, j] : component)
		count += i < j;
	int res = int64_t(count) * (component.size() - count) % P;
	if (count)
		res = (int64_t(res) * inv(component.size())) % P;
	component.clear();
	return res;
}

void Solve()
{
	int res = 0;
	visited.resize(n);
	for (int i = 0; i < n; i++)
		for (int j = 0; j < n; j++)
			visited[i][j] = 0;

	for (int i = 0; i < n; i++)
		for (int j = i + 1; j < n; j++)
			if (!visited[i][j])
				res = (res + Visit(i, j)) % P;

	printf("%d\n", res);
}

int main()
{
	Read();
	Solve();
	return 0;
}