#include<bits/stdc++.h>

#define ll long long
#define mk make_pair
#define fi first
#define se second

using namespace std;

inline int read(){
	int x=0,f=1;char c=getchar();
	for(;(c<'0'||c>'9');c=getchar()){if(c=='-')f=-1;}
	for(;(c>='0'&&c<='9');c=getchar())x=x*10+(c&15);
	return x*f;
}

const int mod=1e9+7;
int ksm(int x,ll y,int p=mod){
	int ans=1;y%=(p-1);
	for(int i=y;i;i>>=1,x=1ll*x*x%p)if(i&1)ans=1ll*ans*x%p;
	return ans%p;
}
int inv(int x,int p=mod){return ksm(x,p-2,p)%p;}
mt19937 rnd(time(0));
int randint(int l,int r){return rnd()%(r-l+1)+l;}
void add(int &x,int v){x+=v;if(x>=mod)x-=mod;}
void Mod(int &x){if(x>=mod)x-=mod;}
int cmod(int x){if(x>=mod)x-=mod;return x;}

template<typename T>void cmax(T &x,T v){x=max(x,v);}
template<typename T>void cmin(T &x,T v){x=min(x,v);}

const int N=105;
int f[2][N][N*N],n,K;

signed main(void){

#ifndef ONLINE_JUDGE
	freopen("in.in","r",stdin);
#endif

	n=read(),K=read();
	
	int cur=0;f[cur][0][0]=1;
	for(int i=n;i>=1;i--){
		memset(f[cur^1],0,sizeof(f[cur^1]));
		for(int j=0;j<=n-i;j++)for(int s=0;s<=n*n;s++)if(f[cur][j][s]){
			int k=n-i-j;
			add(f[cur^1][j+2][s],1ll*f[cur][j][s]*k%mod*k%mod);
			add(f[cur^1][j+1][s+i],2ll*f[cur][j][s]*k%mod*(n-j-k-k)%mod);
			add(f[cur^1][j+1][s+i],1ll*f[cur][j][s]*(n-j-k-k)%mod);
			add(f[cur^1][j][s+i+i],1ll*f[cur][j][s]*(n-j-k-k)%mod*(n-j-k-k-1)%mod);
		}
		cur^=1;
//		cout<<"f "<<i<<" = ";for(int j=0;j<=n;j++)for(int s=0;s<=n*n;s++)if(f[cur][j][s])cout<<"("<<j<<","<<s<<" | "<<f[cur][j][s]<<") ";puts("");
	}
	cout<<f[cur][n][K]<<endl;

	return 0;
}