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#include <bits/stdc++.h>

#define ll long long
#define fors(u, n, s) for(ll u = (s); u < (n); u++)
#define foru(u, n) fors(u, n, 0)
#define vec vector
#define pb push_back
#define f first
#define s second
#define ir(a, b, x) (((a) <= (x)) && ((x) <= (b)))
#define pint pair<int, int>

using namespace std;

const ll M = 1e9+7;

ll inv(ll a) {
  return a <= 1 ? a : M - (long long)(M/a) * inv(M % a) % M;
}

const int N = 4000;
int n;

int parent[N*N];
int rnk[N*N];
ll card[N*N];
ll iv[N*N]; // how many pairs of first > second

int get_parent(int x) {
	if (parent[x] == x) return x;
	parent[x] = get_parent(parent[x]);
	return parent[x];
}

void mrg(int x, int y){
	x = get_parent(x);
	y = get_parent(y);
	if(x==y) return;
	if (rnk[x] < rnk[y]) swap(x, y);
	if(rnk[x] == rnk[y]) rnk[x] ++;
	card[x] += card[y];
	iv[x] += iv[y];
	parent[y] = x;
}

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

inline pint pair_from_int(int x){
	return {x/n, x%n};
}

int perms[N][N];

int perm[N];

const int TRIES = 10;

int main(){
	cin.tie(0); cout.tie(0); ios_base::sync_with_stdio(0);

	int k;
	cin >> n >> k;

	foru(i, k){
		foru(j, n){
			cin >> perms[i][j]; perms[i][j]--;
		}
	}

	random_shuffle(perms, perms+k);

	foru(i, n*n){
		parent[i]=i;
		rnk[i]=1;
		card[i]=1;

		pint p = pair_from_int(i);
		iv[i] = (p.f > p.s);
	}

	foru (k_, k) {
		foru(i, n) perm[i]=perms[k_][i];

		vec<int> non_stable;
		foru(i, n) if(perm[i] != i) non_stable.pb(i);

		bool is_new = true;

		if(k<=30) goto out;

		is_new = false;

		foru(i, n) foru(_i, TRIES){
			int j = rand()%n;

			if(get_parent(int_from_pair(i, j)) != get_parent(int_from_pair(perm[i], perm[j]))){
				is_new = true;
				goto out;
			}
		}

		out:

		int idx = 0;

		if(!is_new) goto skip;

		

		foru(i, n) {
			if(idx != non_stable.size() && i == non_stable[idx]) {
				idx++;
				foru(j, n) {
					int a = int_from_pair(i, j);
					int b = int_from_pair(perm[i], perm[j]);
					mrg(a, b);
				}
			} else {
				for(auto j : non_stable){
					int a = int_from_pair(i, j);
					int b = int_from_pair(perm[i], perm[j]);
					mrg(a, b);
				}
			}
		}

		skip:;
	}

	ll ans = 0;

	foru(i, n) fors(j, n, i+1) {
		int idx = int_from_pair(i, j);
		idx = get_parent(idx);
		ans += iv[idx]*inv(card[idx]);
		ans = ans%M;
	}

	cout << ans;
	
	return 0;
}