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/*
Things to notice:
1. do not calculate useless values
2. do not use similar names
 
Things to check:
1. submit the correct file
2. time (it is log^2 or log)
3. memory
4. prove your naive thoughts 
5. long long
6. corner case like n=0,1,inf or n=m
7. check if there is a mistake in the ds or other tools you use
8. fileio in some oi-contest

9. module on time 
10. the number of a same divisor in a math problem
11. multi-information and queries for dp and ds problems
*/

#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
const int mod=1e9+7;
const int inf=0x3f3f3f3f;
int n,K;
short perm[3005][3005];
int cnt0,cnt1,ans;
bool vis[3005][3005];
int fpow(int x,int b)
{
	if(x==0) return 0;
	if(b==0) return 1;
	int res=1;
	while(b>0)
	{
		if(b&1)	res=1LL*res*x%mod;
		x=1LL*x*x%mod;
		b>>=1;
	}
	return res;
}
void dfs0(short x,short y)
{
	if(x<y) cnt0++;
	else cnt1++;
	vis[x][y]=1;
	short *px=perm[x],*py=perm[y];
	for(short i=1;i<=K;i++) if(!vis[px[i]][py[i]]) dfs0(px[i],py[i]);
}
int a[3005];
mt19937 rnd(114514); 
void solve()
{
	cin>>n>>K;
	for(int i=1;i<=n;i++) a[i]=i;
	for(int i=1;i<=K;i++)
	{
//		for(int j=n;j>=1;j--) swap(a[j],a[rnd()%j+1]);
		for(int j=1;j<=n;j++) cin>>perm[j][i];
	}
	for(int i=1;i<=n;i++) for(int j=i+1;j<=n;j++) if(!vis[i][j])
	{
		cnt0=cnt1=0;
		dfs0(i,j);
//		cout<<i<<" "<<j<<" "<<cnt0<<" "<<cnt1<<"\n";
		ans=(ans+1LL*cnt0*cnt1%mod*fpow(cnt0+cnt1,mod-2)%mod)%mod;
	}
	cout<<ans<<"\n";
}
signed main()
{
//	freopen("input.txt","r",stdin);
	ios::sync_with_stdio(0);
	cin.tie(0);
	int _=1;
//	cin>>_;
	while(_--) solve();
	return 0;
}