#include <bits/stdc++.h>

typedef long long ll;
const int mod = 998244353;
const int N = 1005;

int m, n, a[N];

inline ll qpow(ll x, ll y) {
    ll z = 1;
    for (; y; y >>= 1, x = (x * x) % mod)
        if (y & 1) z = (z * x) % mod;
    return z;
}

int main() {
    scanf("%d", &m);
    if (m == 1) { puts("0"); return 0; }
    for (int i = 1; i <= m; ++i) scanf("%d", &a[i]), n += a[i];
    std::sort(a + 1, a + m + 1);
    a[++m] = n;
    int j = 0, X = n * 2, Y = n + 1;
    ll s = 1, t = 1, ans = 0, tmp = 0;
    for (int i = 1; i <= n; ++i) {
        --X, --Y;
        s = s * X % mod, t = t * Y % mod;
        while (j < m && a[j + 1] == i) {
            ++j;
            tmp = s * qpow(t, mod - 2) % mod - 1;
            if (j != m) ans += tmp;
            else ans += mod - tmp;
            if (ans >= mod) ans -= mod;
        }
    }
    ans = (ans * n) % mod;
    ans = (ans * qpow(n - 1, mod - 2)) % mod;
    ans = (mod - 2 * ans % mod) % mod;
	printf("%lld\n", ans);
	return 0;

}