#include <bits/stdc++.h>
using namespace std;
const int MOD = 998244353;
long long dp[1005][2005][2][2], n, k;
int rec(int x, int val, int a, int b) {
  if (val > k) return 0;
  if (x > n) {
    if (val == k)
      return 1;
    else
      return 0;
  }
  if (dp[x][val][a][b] != -1)
    return dp[x][val][a][b];
  else {
    long long ret = 0;
    if (x == 1) {
      ret += rec(x + 1, val + 1, 0, 0);
      ret += rec(x + 1, val + 2, 0, 1);
      ret += rec(x + 1, val + 2, 1, 0);
      ret += rec(x + 1, val + 1, 1, 1);
    } else {
      if (a == 1 && b == 1) {
        ret += rec(x + 1, val + 1, 0, 0);
        ret += rec(x + 1, val + 1, 1, 0);
        ret += rec(x + 1, val + 1, 0, 1);
        ret += rec(x + 1, val, 1, 1);
      }
      if (a == 0 && b == 0) {
        ret += rec(x + 1, val + 1, 1, 1);
        ret += rec(x + 1, val + 1, 1, 0);
        ret += rec(x + 1, val + 1, 0, 1);
        ret += rec(x + 1, val, 0, 0);
      }
      if (a == 1 && b == 0) {
        ret += rec(x + 1, val, 0, 0);
        ret += rec(x + 1, val, 1, 1);
        ret += rec(x + 1, val, 1, 0);
        ret += rec(x + 1, val + 2, 0, 1);
      }
      if (a == 0 && b == 1) {
        ret += rec(x + 1, val + 2, 1, 0);
        ret += rec(x + 1, val, 0, 0);
        ret += rec(x + 1, val, 0, 1);
        ret += rec(x + 1, val, 1, 1);
      }
    }
    ret %= MOD;
    return dp[x][val][a][b] = ret;
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  memset(dp, -1, sizeof(dp));
  cin >> n >> k;
  cout << rec(1, 0, 0, 0) % MOD << endl;
  return 0;
}
