#include<bits/stdc++.h>
using namespace std;
#ifndef BADGNU
#pragma GCC target("sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#endif
#pragma GCC optimize("Ofast,unroll-loops,fast-math,O3")
#define ll long long
// #define int ll
#define ld long double
#define y1 cheza
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int N=1e5+100;
const int M=5001;
const int B=447;
const int mod=1e9+7;
const ll INF=1e18;
const int dx[]={1,-1,0,0};
const int dy[]={0,0,1,-1};
const double eps=1e-6;
int n,L;
int a[105];
int add(int x,int y){
x%=mod;
y%=mod;
return (x+y)%mod;
}
int dp[2][105][1005][4];
void test(){
cin>>n>>L;
for(int i=1;i<=n;i++){
cin>>a[i];
}
sort(a+1,a+n+1);
if(n==1){
cout<<1<<'\n';
return;
}
dp[1][1][0][0]=1;
dp[1][1][0][1]=2;
for(int i=2;i<=n;i++){
int cur=(i&1);
int prev=(cur^1);
for(int j=1;j<=n;j++){
for(int w=0;w<=L;w++){
for(int k=0;k<=2;k++){
int res=dp[prev][j][w][k];
int to=(2*j-k)*(a[i]-a[i-1])+w;
if(res==0)continue;
if(to<=L){
dp[cur][j+1][to][k]=add(dp[cur][j+1][to][k],(j+1-k)*res);
dp[cur][j+1][to][k+1]=add(dp[cur][j+1][to][k+1],(2-k)*res);
dp[cur][j][to][k]=add(dp[cur][j][to][k],(2*j-k)*res);
dp[cur][j][to][k+1]=add(dp[cur][j][to][k+1],(2-k)*res);
dp[cur][j-1][to][k]=add(dp[cur][j-1][to][k],(j-1)*res);
}
dp[prev][j][w][k]=0;
}
}
}
}
int ans=0;
for(int i=0;i<=L;i++){
ans=add(ans,dp[n&1][1][i][2]);
}
cout<<ans<<'\n';
}
/*
*/
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
// cout.tie(nullptr);
int t2=1;
// cin>>t2;
for(int i=1;i<=t2;i++){
test();
}
}
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