#include<bits/stdc++.h>
#define LL long long
#define LLL __int128
#define uint unsigned
#define ldb long double
#define uLL unsigned long
using namespace std;
const int N=505,M=5005,P=1e9+7;
int f[N][M],C[N][N],ans[N][M];
inline void init(int n,int m){
	f[0][0]=1;
	for(int i=0;i<n;++i)
		for(int j=C[i][0]=1;j<=i;++j)
			(C[i][j]=C[i-1][j-1]+C[i-1][j])>=P&&(C[i][j]-=P);
	for(int i=0;i<n;++i){
		for(int j=i;j>=0&&i-j<=n-i;--j)
			for(int k=m,v=i-j;k>=v*v;--k)if(f[j][k]){
				const int t=f[j][k];f[j][k]=0;
				f[j+2][k]=(f[j+2][k]+1ll*t*v*v)%P;
				if(k+v<=m)f[j+1][k+v]=(f[j+1][k+v]+t*(v+v+1ll))%P;
				if(k+v+v+1<=m)f[j][k+v+v+1]=(f[j][k+v+v+1]+t)%P;
			}
		for(int j=0;j<=m;++j){
			int r=f[i+1][j]+(j<=i?(i-j)&1?C[i][j]:P-C[i][j]:0);
			ans[i+1][j]=(r&1?r>=P?r-P:r+P:r)/2;
		}
		for(int j=1;j<=m;++j)(ans[i+1][j]+=ans[i+1][j-1])>=P&&(ans[i+1][j]-=P);
	}
}
signed main(){
    cin.tie(0)->sync_with_stdio(0);
	init(500,5000);
	int t=1;cin>>t;while(t--){int n,m;cin>>n>>m,cout<<ans[n][m]<<'\n';}
    return 0;
}
/*
*/