import sys
input = sys.stdin.readline

mod = 998244353
n = 2*10**5+5
fact = [1] * (n + 1)
invfact = [1] * (n + 1)
for i in range(1, n):
    fact[i + 1] = ((i+1) * fact[i]) % mod
invfact[n] = pow(fact[n], mod - 2, mod)
for i in range(n - 1, -1, -1):
    invfact[i] = invfact[i + 1] * (i + 1) % mod

def comb(n, r):
    if n < 0 or r < 0 or n - r < 0:
        return 0
    return fact[n] * invfact[r] * invfact[n - r] % mod

def f(N, k):
    ma = (N + 1)//2
    if k > (N + 1 - ma) * ma:
        return -1
    if k == (N + 1 - ma) * ma:
        return ma
    if k == 0:
        return 0
    yes = ma
    no = 0
    while yes - no != 1:
        mid = (yes + no)//2
        if k <= mid * (N + 1 - mid):
            yes = mid
        else:
            no = mid
    if k == yes * (N + 1 - yes):
        return yes
    else:
        return -1

T = int(input())
for _ in range(T):
    N, K = map(int, input().split())
    if N % 2 and K == ((N + 1)//2) ** 2:
        print(comb(N + 1, (N + 1)//2) * pow(2, mod - 2, mod) % mod)
    else:
        print(comb(N + 1, f(N, K)))