from functools import lru_cache
mod = 998244353
@lru_cache(maxsize=None)
def main(n,m):
    if m==1: return 1
    if n==m: return pow(2,n-1,mod)
    return (main(n-1,m-1)+main(n-1,m))%mod
for _ in range(int(input())):
    n,m = map(int,input().split())
    print(main(n,m)*main(n+1,n)%mod)