#pragma GCC optimize ("O3")
#pragma GCC target ("avx")
#include "bits/stdc++.h"

using namespace std;
using ll = long long int;

#define repeat(cnt,l) for(auto cnt=decltype(l)();(cnt)<(l);++(cnt))
#define rrepeat(cnt,l) for(auto cnt=(l)-1;0<=(cnt);--(cnt))


//

const int MD = 1000000007;
int N, K;
int X[100010];


namespace CaseGenerator {
    void case1() {
        K = 100000;
        N = 50000;
        repeat(i, N) X[i] = i * 2 + 1;
    }
    void case2() {
        K = 100000;
        N = 66666;
        repeat(i, 33333) X[i * 2] = i * 3 + 1, X[i * 2 + 1] = i * 3 + 2;
    }
}


void input() {
    cin >> K >> N;
    repeat(i, N) scanf("%d", X + i);
}


//


int dp[100010];
int f[100010];

int solve() {
    fill(dp, dp + K + 1, 0);
    fill(f, f + K + 1, 0);
    repeat(i, N) f[X[i]] = 1;
    dp[0] = 1;
    repeat(k, K) {
        const int v = dp[k];
        repeat(i, K - k + 1) {
            dp[i + k] += v * f[i];
            dp[i + k] -= MD*(dp[i + k] >= MD);
        }
    }
    return dp[K];
}


int solve_nyan(){
    fill(dp, dp + K + 1, 0);
    dp[0] = 1;
    repeat(k, K){
        repeat(i, N){
            if (k + X[i] <= K)
                dp[k+X[i]] = (dp[k+X[i]] + dp[k]) % MD;
        }
    }
    return dp[K];
}


void test(){
    CaseGenerator::case1();
    K = 20000;
    assert(solve() == solve_nyan());
    CaseGenerator::case2();
    K = 31415;
    assert(solve() == solve_nyan());
}


int main() {
    //test();
    // CaseGenerator::case1();

    input();
    cout << solve() << endl;
    //cout << solve_nyan() << endl;

    return 0;
}