#include <bits/stdc++.h>
#include <type_traits>
using namespace std;

using ll = long long;

#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rrep(i, n) for (int i = 1; i <= (n); ++i)
#define drep(i, n) for (int i = (n)-1; i >= 0; --i)
#define ddrep(i, n) for (int i = n; i > 0; --i)
#define srep(i, s, t) for (int i = s; i < t; ++i)
#define ssrep(i, s, t) for (int i = s; i <= t; ++i)

#define rng(a) a.begin(), a.end()
#define rrng(a) a.rbegin(), a.rend()
#define pb push_back
#define eb emplace_back
#define fi first
#define se second

#define chmax(x, y) (x = max(x, y))
#define chmin(x, y) (x = min(x, y))

using pi = pair<int, int>;
using vi = vector<int>;
using vvi = vector<vi>;
using vl = vector<ll>;
using vvl = vector<vl>;
using vs = vector<string>;
using vvs = vector<vs>;
using ld = long double;

template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
    os << "(" << p.first << "," << p.second << ")";
    return os;
}

template <class T> ostream &operator<<(ostream &os, const vector<T> &v) {
    os << "{";
    rep(i, (int)v.size()) {
        if (i)
            os << ",";
        os << v[i];
    }
    os << "}";
    return os;
}

template <typename T, size_t S> void printArray(const T (&array)[S]) {
    for (auto val : array)
        std::cout << val << ", ";
    std::cout << "\n";
}

const int mod = 1e9 + 7;
const int inf = 1e9 + 5;

template <std::uint_fast64_t Modulus> class modint {
    using u64 = std::uint_fast64_t;

public:
    u64 x;

    constexpr modint(const u64 x = 0) noexcept : x(x % Modulus) {}
    constexpr u64 &value() noexcept { return x; }
    constexpr const u64 &value() const noexcept { return x; }
    constexpr modint operator+(const modint rhs) const noexcept {
        return modint(*this) += rhs;
    }
    constexpr modint operator-(const modint rhs) const noexcept {
        return modint(*this) -= rhs;
    }
    constexpr modint operator*(const modint rhs) const noexcept {
        return modint(*this) *= rhs;
    }
    constexpr modint operator/(const modint rhs) const noexcept {
        return modint(*this) /= rhs;
    }
    constexpr modint &operator+=(const modint rhs) noexcept {
        x += rhs.x;
        if (x >= Modulus) {
            x -= Modulus;
        }
        return *this;
    }
    constexpr modint &operator-=(const modint rhs) noexcept {
        if (x < rhs.x) {
            x += Modulus;
        }
        x -= rhs.x;
        return *this;
    }
    constexpr modint &operator*=(const modint rhs) noexcept {
        x = x * rhs.x % Modulus;
        return *this;
    }
    constexpr modint &operator/=(modint rhs) noexcept {
        u64 exp = Modulus - 2;
        while (exp) {
            if (exp % 2) {
                *this *= rhs;
            }
            rhs *= rhs;
            exp /= 2;
        }
        return *this;
    }
};

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    cout << std::setprecision(10);

    modint<mod> ans = 0, sum = 0;
    int n; std::cin >> n;
    vi a(n); rep (i, n) std::cin >> a[i];
    rep(i, n) sum += a[i];
    rep(i, n-1) {
        sum -= a[i];
        ans += (sum * a[i]);
    }
    std::cout << ans.x << "\n";
}


Measured memory_bytes: 3988