#(1/pi)*(1/N)*Integral[1/(x^2+A^2)^m,{x,-Infinity,Infinity}]
#=>cal(N,A,m)

mod=998244353

def minimize(lli):
    if len(lli)==1:
        return lli
    li=lli[:]
    li.sort(key=lambda x:x[1])
    
    while True:
        if li[-1][1]==li[-2][1] and li[-1][2]==li[-2][2]:
            li[-2]=(li[-1][0]*li[-2][0]*pow(li[-1][0]+li[-2][0],-1,mod)%mod, li[-1][1],li[-1][2])
            del li[-1]
    return li


def cal(N,A,m):
    numer=1
    denom=N*pow(A,2*m-1,mod)*pow(4,m-1,mod)%mod
    for i in range(m,2*m-1):
        numer*=i
        numer%=mod
    for i in range(1,m):
        denom*=i
        denom%=mod
    
    return numer*pow(denom,-1,mod)%mod


def change(tuple_1,A2):
    N1,A1,m1=tuple_1
    if A1==A2:
        return [(N1,A1,m1+1)]
    if m1==1:
        return [(N1*(A2**2-A1**2)%mod,A1,1),(-N1*(A2**2-A1**2)%mod,A2,1)]
    else:
        tmp=change((-N1*(A2**2-A1**2)%mod, A1, m1-1), A2)
        return [(N1*(A2**2-A1**2)%mod,A1,m1)]+tmp

n=int(input())
a=list(map(int,input().split()))
a.sort()

li=[(1,a[0],1)]
for i in range(1,n):
    ret=[]
    for tu in li:
        ret+=change(tu,a[i])
    li=ret[:]
    li=minimize(li)
#print(li)
ans=0
for tu in li:
    ans+=cal(*tu)
print(ans%mod)