#define NDEBUG
#pragma warning(disable : 4146)

#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <iomanip>
#include <ios>
#include <iostream>
#include <utility>
#include <vector>

namespace n91 {

using i32 = std::int32_t;
using i64 = std::int64_t;
using u32 = std::uint32_t;
using u64 = std::uint64_t;
using isize = std::ptrdiff_t;
using usize = std::size_t;
using f64 = double;

struct rep {
  struct itr {
    usize i;
    constexpr itr(const usize i) noexcept : i(i) {}
    void operator++() noexcept { ++i; }
    constexpr usize operator*() const noexcept { return i; }
    constexpr bool operator!=(const itr x) const noexcept { return i != x.i; }
  };
  const itr f, l;
  constexpr rep(const usize f, const usize l) noexcept
      : f(std::min(f, l)), l(l) {}
  constexpr auto begin() const noexcept { return f; }
  constexpr auto end() const noexcept { return l; }
};
struct revrep {
  struct itr {
    usize i;
    constexpr itr(const usize i) noexcept : i(i) {}
    void operator++() noexcept { --i; }
    constexpr usize operator*() const noexcept { return i; }
    constexpr bool operator!=(const itr x) const noexcept { return i != x.i; }
  };
  const itr f, l;
  constexpr revrep(const usize f, const usize l) noexcept
      : f(l - 1), l(std::min(f, l) - 1) {}
  constexpr auto begin() const noexcept { return f; }
  constexpr auto end() const noexcept { return l; }
};
template <class T> auto md_vec(const usize n, const T &value) {
  return std::vector<T>(n, value);
}
template <class... Args> auto md_vec(const usize n, Args... args) {
  return std::vector<decltype(md_vec(args...))>(n, md_vec(args...));
}
template <class T> constexpr T difference(const T &a, const T &b) noexcept {
  return a < b ? b - a : a - b;
}
template <class T> void chmin(T &a, const T &b) noexcept {
  if (b < a)
    a = b;
}
template <class T> void chmax(T &a, const T &b) noexcept {
  if (a < b)
    a = b;
}
template <class F> class rec_lambda {
  F f;

public:
  rec_lambda(F &&f_) : f(std::forward<F>(f_)) {}
  template <class... Args> auto operator()(Args &&... args) const {
    return f(*this, std::forward<Args>(args)...);
  }
};
template <class T> T scan() {
  T ret;
  std::cin >> ret;
  return ret;
}
constexpr char eoln = '\n';

i64 floor_div(const i64 n, const i64 d) {
  assert(d != 0);
  return n / d - static_cast<i64>((n ^ d) < 0 && n % d != 0);
}

i64 ceil_div(const i64 n, const i64 d) {
  assert(d != 0);
  return n / d + static_cast<i64>((n ^ d) >= 0 && n % d != 0);
}

#ifdef N91_LOCAL
#define OJ_LOCAL(a, b) b
#else
#define OJ_LOCAL(a, b) a
#endif

} // namespace n91

#include <array>
#include <atcoder/modint>

namespace n91 {

void main_() {
  using mint = atcoder::modint998244353;

  const usize n = scan<usize>();
  const usize m = scan<usize>();

  std::vector<std::vector<mint>> dp(m + 1);
  for (const usize i : rep(0, m + 1)) {
    dp[i].resize(std::min(n + 1, i + 1));
  }
  dp[0][0] = 1;

  const auto get = [](const auto &v, const usize i) {
    return v[std::min(i, v.size() - 1)];
  };

  for (const usize b : rep(1, n + 1)) {
    std::vector<std::vector<mint>> next(m + 1);
    for (const usize i : rep(0, m + 1)) {
      next[i].resize(std::min(n - b + 1, i + 1));
    }
    for (const usize i : rep(0, m + 1)) {
      {
        next[i][0] += 2 * get(dp[i], 1);
      }
      if (next[i].size() == 1) {
        continue;
      }
      for (const usize d : rep(1, next[i].size() - 1)) {
        next[i][d] += next[i][d - 1];
        next[i][d] += dp[i][d + 1];
        next[i][d] -= dp[i][d];
        next[i][d] += get(dp[i - d], d);
      }
      {
        const usize d = next[i].size() - 1;
        next[i][d] += next[i][d - 1];
        next[i][d] += get(dp[i], d + 1);
        next[i][d] -= dp[i][d];
        next[i][d] += get(dp[i - d], d);
      }
    }
    dp = std::move(next);
  }

  std::cout << dp[m][0].val() << eoln;
}

} // namespace n91

int main() {
  //*
  std::ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
  //*/
  std::cout << std::fixed << std::setprecision(20);
  n91::main_();
  return 0;
}