/*
 * @Author: wanggk
 * @Date: 2025-02-05 16:19:34
 * No surrender, no illusions
 * And for better or worse
 */
#include<bits/stdc++.h>
#define Spc putchar(' ')
#define End putchar('\n')
#define For(i,il,ir) for(int i=(il);i<=(ir);++i)
#define Fr(i,il,ir) for(int i=(il);i<(ir);++i)
#define Forr(i,ir,il) for(int i=(ir);i>=(il);--i)
#define ForE(u) for(int i=head[u];~i;i=e[i].nxt)
#define fi first
#define se second
#define mk make_pair
#define pb emplace_back
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
namespace _TvT_{
    template<typename T>
    inline void rd(T& x){
        bool f=0;x=0;char ch=getchar();
        while(ch<'0'||ch>'9'){ if(ch=='-') f=1; ch=getchar(); }
        while(ch>='0'&&ch<='9') x=(x<<1)+(x<<3)+(ch^48),ch=getchar();
        if(f) x=-x;
    }
    template<typename T,typename... Args>
    void rd(T& first,Args&... args){ rd(first),rd(args...); }
    int write_num[50];
    template<typename T>
    inline void write(T x){
        int len=0;
        if(x<0) putchar('-'),x=-x;
        do write_num[len++]=x%10ll; while(x/=10ll);
        while(len--) putchar(write_num[len]+'0');
    }
    template<typename T,typename... Args>
    void write(T first,Args... args){ write(first),Spc,write(args...); }
}using namespace _TvT_;
const ll mod=998244353;
const int maxn=505;
void qadd(ll &x,ll y){ x=(x+y>=mod)?x+y-mod:x+y; }

int n;
int a[maxn],sum;
ll f[maxn][maxn],fac[maxn],inv[maxn];
ll qp(ll x,ll b){ ll res=1ll; x%=mod; for(;b;x=x*x%mod,b>>=1) if(b&1) res=res*x%mod; return res; }
ll C(int x,int y){ return (x<y||x<0||y<0)?0:fac[x]*inv[y]%mod*inv[x-y]%mod; }

signed main()
{
    const int N=500;
    fac[0]=1;For(i,1,N) fac[i]=fac[i-1]*(ll)i%mod;
    inv[N]=qp(fac[N],mod-2);Forr(i,N-1,0) inv[i]=inv[i+1]*(i+1)%mod;

    rd(n);
    For(i,1,n) rd(a[i]),sum+=a[i];
    f[n+1][1]=1;
    Forr(i,n,1) For(j,1,sum+1) if(f[i+1][j])
    {
    	qadd(f[i][j+a[i]],f[i+1][j]); // lft=0
    	For(lft,1,a[i])
        {
        	int front=a[i]-lft;
            For(k,2,j){
                int num=j-k+1; 
                ll tmp=C(num+(lft-1)-1,lft-1);
                qadd(f[i][k+front],f[i+1][j]*tmp%mod);
            }
        }
	}
    ll res=0;
//    For(j,1,sum+1) write(f[1][j]),Spc; End;
    For(j,1,sum+1) qadd(res,f[1][j]);
    write(res),End;
    return 0;
}