using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
//using System.Text;
//using System.Text.RegularExpressions;
//using System.Globalization;
//using System.Diagnostics;
using static System.Console;
using System.Numerics;
//using static System.Math;
//using pair = Pair<int, int>;

class Program
{
    static void Main()
    {
        //SetOut(new StreamWriter(OpenStandardOutput()) { AutoFlush = false });
        new Program().solve();
        Out.Flush();
    }
    Scanner cin = new Scanner();
    readonly int[] dd = { 0, 1, 0, -1, 0 }; //→↓←↑
    readonly int mod = 1000000007;
    void chmax<T>(ref T a, T b) where T : IComparable<T> { a = a.CompareTo(b) < 0 ? b : a; }
    void chmin<T>(ref T a, T b) where T : IComparable<T> { a = a.CompareTo(b) < 0 ? a : b; }

    long calc(int N, int[] X, int[] dp, int p)
    {
        for (int i = 0; i < dp.Length; i++)
        {
            dp[i] = 0;
        }
        dp[0] = 1;

        for (int i = 1; i < dp.Length; i++)
        {
            foreach (var v in X)
            {
                if (i - v >= 0)
                {
                    dp[i] += dp[i - v];
                    dp[i] %= p;
                }
            }
        }
        N--;
        int m = dp.Length;
        long ret = 0;
        for (int i = 0; i < m; i++)
        {
            foreach (var v in X)
            {
                //はじめゼロ、m - 1 からmへの飛び超えNまで
                if (m <= i + v  && i + v <= N)
                {
                    ret += (long)dp[i] * dp[N - (i + v)];
                    ret %= p;
                }
            }
        }

        return ret;
    }
    void solve()
    {
        int N = cin.nextint;
        int M = cin.nextint;
        var X = cin.scanint;

        int m1 = 168647939;
        int m2 = 592951213;
        var dp = new int[(N + 1) / 2 + 1];
        long A = calc(N, X, dp, m1);
        long B = calc(N, X, dp, m2);
        //WriteLine(A + " " + B);

        WriteLine(crt(A, m1, B, m2));
    }


    long gcd(long a, long b)
    {
        return (b != 0) ? gcd(b, a % b) : a;
    }
    long lcm(long a, long b)
    {
        return a / gcd(a, b) * b;
    }
    //ax + by = gcd(a, b)となるx, yを求める
    long extgcd(long a, long b, out long x, out long y)
    {
        long g = a;
        if (b != 0)
        {
            g = extgcd(b, a % b, out y, out x);
            y -= (a / b) * x;
        }
        else
        {
            x = 1;
            y = 0;
        }
        return g;
    }
    BigInteger crt(BigInteger a1, long m1, BigInteger a2, long m2)
    {
        extgcd(m1, m2, out long x, out long y);
        var p = m1 * m2;
        x %= p; y %= p;
        BigInteger ret = a1 * m2 % p * y % p + a2 * m1 % p * x % p;     
        return ((ret % p) + p) % p;
    }

}

class Scanner
{
    string[] s; int i;
    char[] cs = new char[] { ' ' };
    public Scanner() { s = new string[0]; i = 0; }
    public string[] scan { get { return ReadLine().Split(); } }
    public int[] scanint { get { return Array.ConvertAll(scan, int.Parse); } }
    public long[] scanlong { get { return Array.ConvertAll(scan, long.Parse); } }
    public double[] scandouble { get { return Array.ConvertAll(scan, double.Parse); } }
    public string next
    {
        get
        {
            if (i < s.Length) return s[i++];
            string st = ReadLine();
            while (st == "") st = ReadLine();
            s = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
            i = 0;
            return next;
        }
    }
    public int nextint { get { return int.Parse(next); } }
    public long nextlong { get { return long.Parse(next); } }
    public double nextdouble { get { return double.Parse(next); } }
}