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#include<iostream>
#include<vector>
#include<random>
#include<algorithm>

using namespace std;

using ll = long long;

constexpr ll mod = 1'000'000'007;
constexpr int mn = 3'030;
constexpr int pn = mn * mn;

constexpr ll szpotmod(ll a, ll b) {
	if (b == 0) return 1;
	ll p = szpotmod(a, b / 2);
	p = (p * p) % mod;
	if (b & 1) {
		p = (p * a) % mod;
	}
	return p;
}

constexpr ll odw(ll a) {
	return szpotmod(a, mod - 2);
}

bool vis[mn][mn];
int pers[mn][mn];
int  stackx[pn];
int  stacky[pn];
int p = 0;

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	ll n, k;
	cin >> n >> k;
	for(int i = 1; i <= n; i++) {
		for(int j = 1; j <= n; j++) {
			vis[i][j] = false;
		}
	}
	for (int i = 0; i < k; i++) {
		for(int j = 1; j <= n; j++) {
			cin >> pers[j][i];
		}
	}
	ll res = 0;	
	ll sor = 0;
	ll inw = 0;
	ll pom = 0;
	bool sym = false;
	ll r;
	int x, y, u, v;
	for(int i = 1; i <= n; i++) {
		for(int j = i + 1; j <= n; j++) {
			if (vis[i][j] || vis[j][i]) continue;
			sor = 0;
			inw = 0;
			pom = 0;
			sym = false;
			vis[i][j] = true;
			stackx[p] = i;
			stacky[p] = j;
			p++;
			while (p) {
				p--;
				x = stackx[p];
				y = stacky[p];
				if (x < y) sor++;
				else inw++;
				pom++;
				for(int w = 0; w < k; w++) {
					u = pers[x][w];
					v = pers[y][w];
					if (!vis[u][v]) {
						if (vis[v][u]) {
							sym = true;
							continue;
						}
						vis[u][v] = true;
						stackx[p] = u;
						stacky[p] = v;
						p++;
					}
				}
			}
			if (sym) r = pom * odw(2);
			else r = 2 * ((sor * inw) % mod) * odw(sor + inw);
			res = (res + r) % mod;
		}
	}
	cout << res << "\n";
}