N,M,K=map(int,input().split())
A=list(map(int,input().split()))
mod=998244353
v=[0]*(N+1)
u=[0]*(M+1)
result=0
for i in range(M):
  u[A[i]]+=1
for x in range(1,M+1):
  for y in range(1,N+1):
    if x*y>N:
      break
    v[x*y]+=u[x]
p=pow(M,-1,mod)
for x in range(1,N+1):
  count=v[x]
  q=count*p
  q%=mod
  ans=1-pow(1-q,K,mod)
  result+=ans
  result%=mod
print(result)