import java.math.BigInteger; import java.util.Arrays; import java.util.Scanner; import java.util.concurrent.ConcurrentHashMap; public class Main { public static void main(String[] args) { new Main().run(); } void run() { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); int m = sc.nextInt(); int[] x = new int[m]; for (int i = 0; i < m; ++i) x[i] = sc.nextInt(); dp = new int[(n + 1) / 2]; long mo1 = 17 * 9920467; long mo2 = 592951213; long mo3 = mo1 * mo2; long ans1 = solve(mo1, n, m, x); long ans2 = solve(mo2, n, m, x); long f1 = ans1 % mo1 * inv(mo2, mo1) % mo1 * mo2 % mo3; long f2 = inv(mo1, mo2) % mo2 * (ans2 % mo2 - f1 % mo2 + mo2) % mo2 * mo1 % mo3; System.out.println((f1 + f2) % mo3); } long inv(long a, long mo) { a %= mo; // a + 0p = a // 0a + 1p =p long[] v = { 0, 1, mo }; long[] u = { 1, 0, a }; while (v[2] != 1) { if (v[2] < u[2]) { long[] tmp = Arrays.copyOf(v, v.length); v = u; u = tmp; continue; } long coe = v[2] / u[2]; for (int i = 0; i < 3; ++i) { v[i] = v[i] - u[i] * coe; } } return v[0] < 0 ? v[0] + mo : v[0]; } int[] dp; long solve(long mo, int n, int m, int[] x) { Arrays.fill(dp, 0); dp[0] = 1; for (int i = 0; i < dp.length; ++i) { for (int j = 0; j < x.length; ++j) { if (i + x[j] >= dp.length) continue; dp[i + x[j]] = (int) ((dp[i + x[j]] + dp[i]) % mo); } } long ret = 0; for (int i = 0; i < dp.length; ++i) { for (int j = 0; j < m; ++j) { if (x[j] + i < dp.length) continue; ret = (ret + (long) dp[(n - 1) - x[j] - i] * dp[i] % mo) % mo; } } return ret; } class BIT { int n; int[] a; public BIT(int n_) { n = n_; a = new int[n + 1]; } void add(int k, int add) { ++k; while (k < a.length) { a[k] += add; k += k & -k; } } int sum(int k) { ++k; int ret = 0; while (k > 0) { ret += a[k]; k -= k & -k; } return ret; } int sum(int a, int b) { return sum(b - 1) - sum(a - 1); } } void tr(Object... objects) { System.out.println(Arrays.deepToString(objects)); } }