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

using namespace std;

#define repeat(cnt,l) for(auto cnt=decltype(l)();(cnt)<(l);++(cnt))


//

const int MD = 100000007;
int N, K;
int X[100010];


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


//


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

__attribute__((target("avx")))
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 main() {

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

    return 0;
}