#include <bits/stdc++.h>
using namespace std;
typedef long long lint;
typedef pair<int, int> pi;
const int MAXN = 3005;
const int mod = 1e9 + 7;
namespace fft{
typedef complex<double> base;
void fft(vector<base> &a, bool inv){
int n = a.size(), j = 0;
for(int i=1; i<n; i++){
int bit = (n >> 1);
while(j >= bit){
j -= bit;
bit >>= 1;
}
j += bit;
if(i < j) swap(a[i], a[j]);
}
for(int i=2; i<=n; i<<=1){
double ang = 2 * acos(-1) / i * (inv ? -1 : 1);
base x(cos(ang), sin(ang));
for(int j=0; j<n; j+=i){
base y(1);
for(int k=0; k<i/2; k++){
base u = a[j+k], v = a[j+k+i/2] * y;
a[j+k] = u+v;
a[j+k+i/2] = u-v;
y *= x;
}
}
}
if(inv) for(int i=0; i<n; i++) a[i] /= n;
}
vector<lint> multiply(vector<lint> &v, vector<lint> &w){
vector<base> fv(v.begin(), v.end()), fw(w.begin(), w.end());
int n = 1;
while(n < max(v.size(), w.size())) n <<= 1;
n <<= 1;
fv.resize(n);
fw.resize(n);
fft(fv, 0);
fft(fw, 0);
for(int i=0; i<n; i++) fv[i] *= fw[i];
fft(fv, 1);
vector<lint> ret(n);
for(int i=0; i<n; i++) ret[i] = round(fv[i].real());
return ret;
}
vector<lint> multiply(vector<lint> &v, vector<lint> &w, lint mod){
int n = 1;
while(n < max(v.size(), w.size())) n <<= 1;
n <<= 1;
vector<base> v1(n), v2(n);
vector<base> r1(n), r2(n);
for(int i=0; i<v.size(); i++){
v1[i] = base(v[i] >> 15, v[i] & 32767);
}
for(int i=0; i<w.size(); i++){
v2[i] = base(w[i] >> 15, w[i] & 32767);
}
fft(v1, 0);
fft(v2, 0);
for(int i=0; i<n; i++){
int j = (i ? (n - i) : i);
base ans1 = (v1[i] + conj(v1[j])) * base(0.5, 0);
base ans2 = (v1[i] - conj(v1[j])) * base(0, -0.5);
base ans3 = (v2[i] + conj(v2[j])) * base(0.5, 0);
base ans4 = (v2[i] - conj(v2[j])) * base(0, -0.5);
r1[i] = (ans1 * ans3) + (ans1 * ans4) * base(0, 1);
r2[i] = (ans2 * ans3) + (ans2 * ans4) * base(0, 1);
}
fft(r1, 1);
fft(r2, 1);
vector<lint> ret(n);
for(int i=0; i<n; i++){
lint av = (lint)round(r1[i].real());
lint bv = (lint)round(r1[i].imag()) + (lint)round(r2[i].real());
lint cv = (lint)round(r2[i].imag());
av %= mod, bv %= mod, cv %= mod;
ret[i] = (av << 30) + (bv << 15) + cv;
ret[i] %= mod;
ret[i] += mod;
ret[i] %= mod;
}
return ret;
}
}
lint ipow(lint x, lint p){
lint ret = 1, piv = x % mod;
while(p){
if(p&1) ret *= piv;
piv *= piv;
ret %= mod;
piv %= mod;
p >>= 1;
}
return ret % mod;
}
lint fact[MAXN], invf[MAXN];
lint bino(int x, int y){
return fact[x] * (invf[x-y] * invf[y] % mod) % mod;
}
int n, l;
int cnt[MAXN];
lint dp[12][MAXN], func[MAXN];
vector<lint> solve(int x, int c){
if(c == 0){
vector<lint> ret(l + 1);
ret[0] = 1;
return ret;
}
if(c % 2 == 1){
vector<lint> a = solve(x, c-1);
vector<lint> b;
for(int i=0; i<=l; i++){
a[i] = (a[i] * invf[i]) % mod;
b.push_back(i < x ? 0 : invf[i]);
}
auto ret = fft::multiply(a, b, mod);
ret.resize(l + 1);
for(int i=0; i<=l; i++){
ret[i] %= mod;
ret[i] *= fact[i];
ret[i] %= mod;
}
return ret;
}
else{
auto tmp = solve(x, c / 2);
for(int i=0; i<=l; i++) tmp[i] = (tmp[i] * invf[i]) % mod;
auto ret = fft::multiply(tmp, tmp, mod);
ret.resize(l + 1);
for(int i=0; i<=l; i++){
ret[i] %= mod;
ret[i] *= fact[i];
ret[i] %= mod;
}
return ret;
}
}
int main(){
fact[0] = invf[0] = 1;
for(int i=1; i<MAXN; i++){
fact[i] = fact[i-1] * i % mod;
invf[i] = ipow(fact[i], mod - 2);
}
cin >> n >> l;
for(int i=0; i<n; i++){
int x;
cin >> x;
cnt[x]++;
}
dp[0][0] = 1;
for(int i=0; i<=10; i++){
vector<lint> func = solve(i, cnt[i]);
vector<lint> a, b;
for(int j=0; j<=l; j++){
a.push_back(func[j] * invf[j] % mod);
b.push_back(dp[i][j] * invf[j] % mod);
}
auto ret = fft::multiply(a, b, mod);
for(int j=0; j<=l; j++) dp[i+1][j] = ((ret[j] % mod) * fact[j] % mod);
}
dp[11][l] *= ipow(ipow(n, l), mod - 2);
dp[11][l] %= mod;
cout << dp[11][l];
}
