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

mod=998244353

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*i
        denom%=mod
    return numer*pow(denom,-1,mod)%mod



def change(tuple_1,A2):
    N1,A1,m1=tuple_1
    if m1==1:
        return [(N1*(A2**2-A1**2),A1,1),(-N1*(A2**2-A1**2),A2,1)]
    else:
        tmp=change((-N1*(A2**2-A1**2), A1, m1-1), A2)
        return [(N1*(A2**2-A1**2),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[:]
#print(li)
ans=0
for tu in li:
    ans+=cal(*tu)
print(ans%mod)