#include<cstdio>
int n,k,x,d,i;
int main()
{
	freopen("permutari2.in","r",stdin);
	freopen("permutari2.out","w",stdout);
	scanf("%d%d",&n,&k);
	if(n==k) 
		printf("%d\n",1);
	else if(n-k==1)
		printf("%d\n",k);
	else if(n-k==2)
	{
		x=3; d=4;
		for(i=1;i<k;i++)
		{
			x=x+d;
			x=x%10007;
			d++;
		}
		printf("%d\n",x);
	}
	else if(n-k==3)
	{
		x=71; d=106;
		for(i=1;i<k;i++)
		{
			x=x+d;
			x=x%10007;
			d=d+9+i;
		}
		printf("%d\n",x);
	}
	return 0;
}