n,k=map(int,input().split());mod=10**9+7
dp=[[0]*(n*100+1) for i in range(n+1)];p=0;dp[0][0]=1
for i in list(map(int,input().split())):
    dp2=[[0]*(n*100+1) for i in range(n+1)]
    for j in range(p+1):
        for l in range(p*100+1):
            dp2[j+1][l+i]+=dp[j][l]
            dp2[j+1][l+i]%=mod
            dp2[j][l]+=dp[j][l]
            dp2[j][l]%=mod
    dp=dp2;p+=1
ans=0
for i in range(1,n+1):
    for j in range(i*k,n*100+1):
        ans+=dp[i][j]
print(ans%mod)