N,K = map(int,input().split())
A = [[0]*(4*N) for _ in range(4*N)]
for i in range(4*N):
    for j in range(4*N):
        if i == 0:
            if j % 4 == 0:
                A[i][j] = 4
            else:
                A[i][j] = 3
        if i == 1:
            if j % 4 == 0:
                A[i][j] = 0
            else:
                A[i][j] = 1
        if i == j+1:
            A[i][j] = 1
            
mod = 998244353
def mul(A,B):
    C = [[0]*(4*N) for _ in range(4*N)]
    for i in range(4*N):
        for j in range(4*N):
            for k in range(4*N):
                C[i][j] += A[i][k]*B[k][j]
                C[i][j] %= mod
    return C

A_pow = [[0]*(4*N) for _ in range(4*N)]
for i in range(4*N):
    A_pow[i][i] = 1
pw = K-1
while pw > 0:
    if pw & 1:
        A_pow = mul(A_pow,A)
    pw >>= 1
    A = mul(A,A)

ans = (A_pow[4*N-1][0]*pow(5,-K,mod)) % mod
print(ans)