using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using static System.Math;
using System.Text;
using System.Threading;
using System.Globalization;
using System.Runtime.CompilerServices;
using Library;

namespace Program
{
    public static class ProblemC
    {
        static bool SAIKI = false;
        static public int numberOfRandomCases = 0;
        static public void MakeTestCase(List<string> _input, List<string> _output, ref Func<string[], bool> _outputChecker)
        {
        }
        static public void Solve()
        {
            var N = NN;
            var AList = NNList(N);
            var mult = LIB_NTT.Multiply(AList, AList, 1000000007);
            LIB_Mod ans = 0;
            foreach (var item in mult)
            {
                ans += item;
            }
            foreach (var item in AList)
            {
                ans -= item * item;
            }
            Console.WriteLine(ans / 2);
        }
        class Printer : StreamWriter
        {
            public override IFormatProvider FormatProvider { get { return CultureInfo.InvariantCulture; } }
            public Printer(Stream stream) : base(stream, new UTF8Encoding(false, true)) { base.AutoFlush = false; }
            public Printer(Stream stream, Encoding encoding) : base(stream, encoding) { base.AutoFlush = false; }
        }
        static LIB_FastIO fastio = new LIB_FastIODebug();
        static public void Main(string[] args) { if (args.Length == 0) { fastio = new LIB_FastIO(); Console.SetOut(new Printer(Console.OpenStandardOutput())); } if (SAIKI) { var t = new Thread(Solve, 134217728); t.Start(); t.Join(); } else Solve(); Console.Out.Flush(); }
        static long NN => fastio.Long();
        static double ND => fastio.Double();
        static string NS => fastio.Scan();
        static long[] NNList(long N) => Repeat(0, N).Select(_ => NN).ToArray();
        static double[] NDList(long N) => Repeat(0, N).Select(_ => ND).ToArray();
        static string[] NSList(long N) => Repeat(0, N).Select(_ => NS).ToArray();
        static long Count<T>(this IEnumerable<T> x, Func<T, bool> pred) => Enumerable.Count(x, pred);
        static IEnumerable<T> Repeat<T>(T v, long n) => Enumerable.Repeat<T>(v, (int)n);
        static IEnumerable<int> Range(long s, long c) => Enumerable.Range((int)s, (int)c);
        static IOrderedEnumerable<T> OrderByRand<T>(this IEnumerable<T> x) => Enumerable.OrderBy(x, _ => xorshift);
        static IOrderedEnumerable<T> OrderBy<T>(this IEnumerable<T> x) => Enumerable.OrderBy(x.OrderByRand(), e => e);
        static IOrderedEnumerable<T1> OrderBy<T1, T2>(this IEnumerable<T1> x, Func<T1, T2> selector) => Enumerable.OrderBy(x.OrderByRand(), selector);
        static IOrderedEnumerable<T> OrderByDescending<T>(this IEnumerable<T> x) => Enumerable.OrderByDescending(x.OrderByRand(), e => e);
        static IOrderedEnumerable<T1> OrderByDescending<T1, T2>(this IEnumerable<T1> x, Func<T1, T2> selector) => Enumerable.OrderByDescending(x.OrderByRand(), selector);
        static IOrderedEnumerable<string> OrderBy(this IEnumerable<string> x) => x.OrderByRand().OrderBy(e => e, StringComparer.OrdinalIgnoreCase);
        static IOrderedEnumerable<T> OrderBy<T>(this IEnumerable<T> x, Func<T, string> selector) => x.OrderByRand().OrderBy(selector, StringComparer.OrdinalIgnoreCase);
        static IOrderedEnumerable<string> OrderByDescending(this IEnumerable<string> x) => x.OrderByRand().OrderByDescending(e => e, StringComparer.OrdinalIgnoreCase);
        static IOrderedEnumerable<T> OrderByDescending<T>(this IEnumerable<T> x, Func<T, string> selector) => x.OrderByRand().OrderByDescending(selector, StringComparer.OrdinalIgnoreCase);
        static string Join<T>(this IEnumerable<T> x, string separator = "") => string.Join(separator, x);
        static uint xorshift { get { _xsi.MoveNext(); return _xsi.Current; } }
        static IEnumerator<uint> _xsi = _xsc();
        static IEnumerator<uint> _xsc() { uint x = 123456789, y = 362436069, z = 521288629, w = (uint)(DateTime.Now.Ticks & 0xffffffff); while (true) { var t = x ^ (x << 11); x = y; y = z; z = w; w = (w ^ (w >> 19)) ^ (t ^ (t >> 8)); yield return w; } }
    }
}
namespace Library {
    class LIB_NTT
    {
        uint mod;
        uint root;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        LIB_NTT(uint mod, uint root) { this.mod = mod; this.root = root; }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        uint add(uint x, uint y) => (x + y < mod) ? (x + y) : (x + y - mod);
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        uint sub(uint x, uint y) => (x >= y) ? (x - y) : (mod - y + x);
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        uint mul(uint x, uint y) => (uint)((ulong)x * y % mod);
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        uint pow(uint x, uint n)
        {
            uint res = 1;
            while (n > 0)
            {
                if ((n & 1) != 0) res = mul(res, x);
                x = mul(x, x);
                n >>= 1;
            }
            return res;
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        uint inverse(uint x)
        {
            long b = mod, r = 1, u = 0, t = 0, x2 = x;
            while (b > 0)
            {
                var q = x2 / b;
                t = u;
                u = r - q * u;
                r = t;
                t = b;
                b = x2 - q * b;
                x2 = t;
            }
            return (uint)(r < 0 ? r + mod : r);
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        void ntt(ref uint[] a, bool rev = false)
        {
            var n = (uint)a.Length;
            if (n == 1) return;
            var b = new uint[n];
            var s = pow(root, rev ? (mod - 1 - (mod - 1) / n) : (mod - 1) / n);
            var kp = Enumerable.Repeat((uint)1, (int)(n / 2 + 1)).ToArray();
            uint i, j, k, l, r;
            for (i = 0; i < n / 2; ++i) kp[i + 1] = mul(kp[i], s);
            for (i = 1, l = n / 2; i < n; i <<= 1, l >>= 1)
            {
                for (j = 0, r = 0; j < l; ++j, r += i)
                {
                    for (k = 0, s = kp[i * j]; k < i; ++k)
                    {
                        var p = a[k + r]; var q = a[k + r + n / 2];
                        b[k + 2 * r] = add(p, q);
                        b[k + 2 * r + i] = mul(sub(p, q), s);
                    }
                }
                var t = a; a = b; b = t;
            }
            if (rev)
            {
                s = inverse(n);
                for (i = 0; i < n; ++i) a[i] = mul(a[i], s);
            }
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static uint[] Multiply(uint[] a, uint[] b, uint mod, uint root)
        {
            var n = a.Length + b.Length - 1;
            var t = 1;
            while (t < n) t <<= 1;
            var na = new uint[t];
            var nb = new uint[t];
            for (var i = 0; i < a.Length; ++i) na[i] = a[i];
            for (var i = 0; i < b.Length; ++i) nb[i] = b[i];
            var ntt = new LIB_NTT(mod, root);
            ntt.ntt(ref na);
            ntt.ntt(ref nb);
            for (var i = 0; i < t; ++i) na[i] = ntt.mul(na[i], nb[i]);
            ntt.ntt(ref na, true);
            return na.Take(n).ToArray();
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public long[] Multiply(long[] a, long[] b) => Multiply(a.Select(e => (uint)e).ToArray(), b.Select(e => (uint)e).ToArray(), 998244353, 3).Select(e => (long)e).ToArray();
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public long[] Multiply(long[] a, long[] b, long mod)
        {
            if (mod == 998244353) return Multiply(a, b);
            var m1 = new LIB_NTT(1045430273, 3);
            var m2 = new LIB_NTT(1051721729, 6);
            var m3 = new LIB_NTT(1053818881, 7);
            var uinta = a.Select(e => (uint)e).ToArray();
            var uintb = b.Select(e => (uint)e).ToArray();
            var x = Multiply(uinta, uintb, m1.mod, m1.root);
            var y = Multiply(uinta, uintb, m2.mod, m2.root);
            var z = Multiply(uinta, uintb, m3.mod, m3.root);
            var m1_inv_m2 = m2.inverse(m1.mod);
            var m12_inv_m3 = m3.inverse(m3.mul(m1.mod, m2.mod));
            var m12_mod = (long)m1.mod * m2.mod % mod;
            var ret = new long[x.Length];
            for (var i = 0; i < x.Length; ++i)
            {
                var v1 = m2.mul(m2.sub(m2.add(y[i], m2.mod), x[i]), m1_inv_m2);
                var v2 = m3.mul(m3.sub(m3.sub(m3.add(z[i], m3.mod), x[i]), m3.mul(m1.mod, v1)), m12_inv_m3);
                ret[i] = (x[i] + ((long)m1.mod * v1 % mod) + ((long)m12_mod * v2 % mod)) % mod;
            }
            return ret;
        }
    }
    class LIB_FastIO
    {
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public LIB_FastIO() { str = Console.OpenStandardInput(); }
        readonly Stream str;
        readonly byte[] buf = new byte[1024];
        int len, ptr;
        public bool isEof = false;
        public bool IsEndOfStream
        {
            [MethodImpl(MethodImplOptions.AggressiveInlining)]
            get { return isEof; }
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        byte read()
        {
            if (isEof) throw new EndOfStreamException();
            if (ptr >= len)
            {
                ptr = 0;
                if ((len = str.Read(buf, 0, 1024)) <= 0)
                {
                    isEof = true;
                    return 0;
                }
            }
            return buf[ptr++];
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        char Char()
        {
            byte b = 0;
            do b = read();
            while (b < 33 || 126 < b);
            return (char)b;
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        virtual public string Scan()
        {
            var sb = new StringBuilder();
            for (var b = Char(); b >= 33 && b <= 126; b = (char)read())
                sb.Append(b);
            return sb.ToString();
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        virtual public long Long()
        {
            long ret = 0; byte b = 0; var ng = false;
            do b = read();
            while (b != '-' && (b < '0' || '9' < b));
            if (b == '-') { ng = true; b = read(); }
            for (; true; b = read())
            {
                if (b < '0' || '9' < b)
                    return ng ? -ret : ret;
                else ret = ret * 10 + b - '0';
            }
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        virtual public double Double() { return double.Parse(Scan(), CultureInfo.InvariantCulture); }
    }
    class LIB_FastIODebug : LIB_FastIO
    {
        Queue<string> param = new Queue<string>();
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        string NextString() { if (param.Count == 0) foreach (var item in Console.ReadLine().Split(' ')) param.Enqueue(item); return param.Dequeue(); }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public LIB_FastIODebug() { }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override string Scan() => NextString();
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override long Long() => long.Parse(NextString());
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override double Double() => double.Parse(NextString());
    }
    partial struct LIB_Mod : IEquatable<LIB_Mod>, IEquatable<long>
    {
        static public long _mod = 1000000007; long v;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public LIB_Mod(long x)
        {
            if (x < _mod && x >= 0) v = x;
            else if ((v = x % _mod) < 0) v += _mod;
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public implicit operator LIB_Mod(long x) => new LIB_Mod(x);
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public implicit operator long(LIB_Mod x) => x.v;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void Add(LIB_Mod x) { if ((v += x.v) >= _mod) v -= _mod; }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void Sub(LIB_Mod x) { if ((v -= x.v) < 0) v += _mod; }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void Mul(LIB_Mod x) => v = (v * x.v) % _mod;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void Div(LIB_Mod x) => v = (v * Inverse(x.v)) % _mod;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod operator +(LIB_Mod x, LIB_Mod y) { var t = x.v + y.v; return t >= _mod ? new LIB_Mod { v = t - _mod } : new LIB_Mod { v = t }; }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod operator -(LIB_Mod x, LIB_Mod y) { var t = x.v - y.v; return t < 0 ? new LIB_Mod { v = t + _mod } : new LIB_Mod { v = t }; }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod operator *(LIB_Mod x, LIB_Mod y) => x.v * y.v;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod operator /(LIB_Mod x, LIB_Mod y) => x.v * Inverse(y.v);
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public bool operator ==(LIB_Mod x, LIB_Mod y) => x.v == y.v;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public bool operator !=(LIB_Mod x, LIB_Mod y) => x.v != y.v;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public long Inverse(long x)
        {
            long b = _mod, r = 1, u = 0, t = 0;
            while (b > 0)
            {
                var q = x / b;
                t = u;
                u = r - q * u;
                r = t;
                t = b;
                b = x - q * b;
                x = t;
            }
            return r < 0 ? r + _mod : r;
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public bool Equals(LIB_Mod x) => v == x.v;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public bool Equals(long x) => v == x;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override bool Equals(object x) => x == null ? false : Equals((LIB_Mod)x);
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override int GetHashCode() => v.GetHashCode();
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override string ToString() => v.ToString();
        static List<LIB_Mod> _fact = new List<LIB_Mod>() { 1 };
        static long _factm = _mod;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static void B(long n)
        {
            if (_factm != _mod) _fact = new List<LIB_Mod>() { 1 };
            if (n >= _fact.Count)
                for (int i = _fact.Count; i <= n; ++i)
                    _fact.Add(_fact[i - 1] * i);
            _factm = _mod;
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod Comb(long n, long k)
        {
            B(n);
            if (n == 0 && k == 0) return 1;
            if (n < k || n < 0) return 0;
            return _fact[(int)n] / _fact[(int)(n - k)] / _fact[(int)k];
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod CombOK(long n, long k)
        {
            LIB_Mod ret = 1;
            for (var i = 0; i < k; i++) ret *= n - i;
            for (var i = 1; i <= k; i++) ret /= i;
            return ret;
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod Perm(long n, long k)
        {
            B(n);
            if (n == 0 && k == 0) return 1;
            if (n < k || n < 0) return 0;
            return _fact[(int)n] / _fact[(int)(n - k)];
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod KanzenPerm(long n) => Enumerable.Range(0, (int)n + 1).Aggregate((LIB_Mod)0, (a, e) => a + (1 - ((e & 1) << 1)) * LIB_Mod.Comb(n, e) * LIB_Mod.Perm(n - e, n - e));
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static public LIB_Mod Pow(LIB_Mod x, long y)
        {
            LIB_Mod a = 1;
            while (y != 0)
            {
                if ((y & 1) == 1) a.Mul(x);
                x.Mul(x);
                y >>= 1;
            }
            return a;
        }
    }
}


Measured memory_bytes: 62844