#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")

////////////////////////////////////////////////////////////////////////////////
template <unsigned M_> struct ModInt {
  static constexpr unsigned M = M_;
  unsigned x;
  constexpr ModInt() : x(0U) {}
  constexpr ModInt(unsigned x_) : x(x_ % M) {}
  constexpr ModInt(unsigned long long x_) : x(x_ % M) {}
  constexpr ModInt(int x_) : x(((x_ %= static_cast<int>(M)) < 0) ? (x_ + static_cast<int>(M)) : x_) {}
  constexpr ModInt(long long x_) : x(((x_ %= static_cast<long long>(M)) < 0) ? (x_ + static_cast<long long>(M)) : x_) {}
  ModInt &operator+=(const ModInt &a) { x = ((x += a.x) >= M) ? (x - M) : x; return *this; }
  ModInt &operator-=(const ModInt &a) { x = ((x -= a.x) >= M) ? (x + M) : x; return *this; }
  ModInt &operator*=(const ModInt &a) { x = (static_cast<unsigned long long>(x) * a.x) % M; return *this; }
  ModInt &operator/=(const ModInt &a) { return (*this *= a.inv()); }
  ModInt pow(long long e) const {
    if (e < 0) return inv().pow(-e);
    ModInt a = *this, b = 1U; for (; e; e >>= 1) { if (e & 1) b *= a; a *= a; } return b;
  }
  ModInt inv() const {
    unsigned a = M, b = x; int y = 0, z = 1;
    for (; b; ) { const unsigned q = a / b; const unsigned c = a - q * b; a = b; b = c; const int w = y - static_cast<int>(q) * z; y = z; z = w; }
    assert(a == 1U); return ModInt(y);
  }
  ModInt operator+() const { return *this; }
  ModInt operator-() const { ModInt a; a.x = x ? (M - x) : 0U; return a; }
  ModInt operator+(const ModInt &a) const { return (ModInt(*this) += a); }
  ModInt operator-(const ModInt &a) const { return (ModInt(*this) -= a); }
  ModInt operator*(const ModInt &a) const { return (ModInt(*this) *= a); }
  ModInt operator/(const ModInt &a) const { return (ModInt(*this) /= a); }
  template <class T> friend ModInt operator+(T a, const ModInt &b) { return (ModInt(a) += b); }
  template <class T> friend ModInt operator-(T a, const ModInt &b) { return (ModInt(a) -= b); }
  template <class T> friend ModInt operator*(T a, const ModInt &b) { return (ModInt(a) *= b); }
  template <class T> friend ModInt operator/(T a, const ModInt &b) { return (ModInt(a) /= b); }
  explicit operator bool() const { return x; }
  bool operator==(const ModInt &a) const { return (x == a.x); }
  bool operator!=(const ModInt &a) const { return (x != a.x); }
  friend std::ostream &operator<<(std::ostream &os, const ModInt &a) { return os << a.x; }
};
////////////////////////////////////////////////////////////////////////////////

constexpr unsigned MO = 1000000007;
using Mint = ModInt<MO>;


int N, L;
vector<int> A;

/*
  k: building k segments
  s: # ends closed
  c: cost
  
  incur cost (2k - s)
  use k ==> need cost 2+4+...+(2k-2)+...+4+2 = 2(k-1)^2
*/
constexpr int K = 24;
Mint dp[2][K + 1][3][1010];

int main() {
  for (; ~scanf("%d%d", &N, &L); ) {
    A.resize(N);
    for (int i = 0; i < N; ++i) {
      scanf("%d", &A[i]);
    }
    sort(A.begin(), A.end());
    
    Mint ans = 0;
    if (N == 1) {
      ans = 1;
    } else {
      memset(dp, 0, sizeof(dp));
      dp[0][0][0][0] += 1;
      for (int i = 0; i < N; ++i) {
        if (i) {
          for (int k = 0; k < K; ++k) for (int s = 0; s <= 2; ++s) if (2 * k - s >= 0) {
            const int dc = (2 * k - s) * (A[i] - A[i - 1]);
            for (int c = 0; c < dc; ++c) dp[0][k][s][c] = 0;
            for (int c = dc; c <= L; ++c) dp[0][k][s][c] = dp[1][k][s][c - dc];
            for (int c = 0; c <= L; ++c) dp[1][k][s][c] = 0;
          }
        }
// for(int k=0;k<K;++k)for(int s=0;s<=2;++s)for(int c=0;c<=L;++c)if(dp[0][k][s][c])cerr<<i<<" "<<k<<" "<<s<<" "<<c<<": "<<dp[0][k][s][c]<<endl;
        for (int k = 0; k < K; ++k) for (int s = 0; s <= 2; ++s) if (2 * k - s >= 0) {
          auto go = [&](int kk, int ss, Mint wt) -> void {
            if (wt) {
              for (int c = 0; c <= L; ++c) {
                dp[1][kk][ss][c] += dp[0][k][s][c] * wt;
              }
            }
          };
          go(k + 1, s, k + 1 - s);
          go(k + 1, s + 1, 2 - s);
          go(k, s, 2 * k - s);
          go(k, s + 1, 2 - s);
          if (k) go(k - 1, s, k - 1);
        }
      }
// pv(dp[1][1][2],dp[1][1][2]+(L+1));
      for (int c = 0; c <= L; ++c) {
        ans += dp[1][1][2][c];
      }
    }
    printf("%u\n", ans.x);
  }
  return 0;
}