#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int, int>;
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
const int mod = 1000000007;
struct mint {
  ll x;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint& operator+=(const mint a) {
    if ((x += a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator-=(const mint a) {
    if ((x += mod - a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const { return mint(*this) += a; }
  mint operator-(const mint a) const { return mint(*this) -= a; }
  mint operator*(const mint a) const { return mint(*this) *= a; }
  mint pow(ll t) const {
    if (!t) return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1) a *= *this;
    return a;
  }
  mint inv() const { return pow(mod - 2); }
  mint& operator/=(const mint a) { return *this *= a.inv(); }
  mint operator/(const mint a) const { return mint(*this) /= a; }
};
istream& operator>>(istream& is, const mint& a) { return is >> a.x; }
ostream& operator<<(ostream& os, const mint& a) { return os << a.x; }
int main() {
  int n, s;
  cin >> n >> s;
  vector<int> a(n);
  for (int((i)) = (int)(0); ((i)) < (int)((n)); ++((i))) cin >> a[i];
  vector<mint> q(s + 1);
  mint ans = 0;
  for (int((i)) = (int)(0); ((i)) < (int)((n)); ++((i))) {
    q[0] += 1;
    vector<mint> q2(s + 1);
    for (int((j)) = (int)(0); ((j)) < (int)((s + 1)); ++((j))) {
      q2[j] += q[j];
      if (j + a[i] <= s) q2[j + a[i]] += q[j];
    }
    q = q2;
    ans += q[s];
  }
  return 0;
}
