#include <bits/stdc++.h>
using namespace std;
#if __has_include(<atcoder/all>)
#include <atcoder/all>
using namespace atcoder;
#endif
using ll = long long;
using ld = long double;
using ull = unsigned long long;
#define endl "\n"
typedef pair<int, int> Pii;
#define REP(i, n) for (int i = 0; i < (n); ++i)
#define REP3(i, m, n) for (int i = (m); (i) < int(n); ++ (i))
#define FOR(i,a,b) for(ll i=a;i<=(ll)(b);i++)
#define rep(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define ALL(x) begin(x), end(x)
#define rrep(i,a,b) for(int i=a;i>=b;i--)
#define fore(i,a) for(auto &i:a)
#define all(s) (s).begin(),(s).end()
#define drep2(i, m, n) for (int i = (m)-1; i >= (n); --i)
#define drep(i, n) drep2(i, n, 0)
#define rever(vec) reverse(vec.begin(), vec.end())
#define sor(vec) sort(vec.begin(), vec.end())
#define fi first
#define se second
#define pb push_back
#define P pair<ll,ll>
#define PQminll priority_queue<ll, vector<ll>, greater<ll>>
#define PQmaxll priority_queue<ll,vector<ll>,less<ll>>
#define PQminP priority_queue<P, vector<P>, greater<P>>
#define PQmaxP priority_queue<P,vector<P>,less<P>>
#define NP next_permutation
//const ll mod = 1000000009;
const ll mod = 998244353;
//const ll mod = 1000000007;
const ll inf = 4100000000000000000ll;
const ld eps = ld(0.00000000001);
static const long double pi = 3.141592653589793;
template<class T>void vcin(vector<T> &n){for(int i=0;i<int(n.size());i++) cin>>n[i];}
template<class T,class K>void vcin(vector<T> &n,vector<K> &m){for(int i=0;i<int(n.size());i++) cin>>n[i]>>m[i];}
template<class T>void vcout(vector<T> &n){for(int i=0;i<int(n.size());i++){cout<<n[i]<<" ";}cout<<endl;}
template<class T>void vcin(vector<vector<T>> &n){for(int i=0;i<int(n.size());i++){for(int j=0;j<int(n[i].size());j++){cin>>n[i][j];}}}
template<class T>void vcout(vector<vector<T>> &n){for(int i=0;i<int(n.size());i++){for(int j=0;j<int(n[i].size());j++){cout<<n[i][j]<<" ";}cout<<endl;}cout<<endl;}
void yes(bool a){cout<<(a?"yes":"no")<<endl;}
void YES(bool a){cout<<(a?"YES":"NO")<<endl;}
void Yes(bool a){cout<<(a?"Yes":"No")<<endl;}
void possible(bool a){ cout<<(a?"possible":"impossible")<<endl; }
void Possible(bool a){ cout<<(a?"Possible":"Impossible")<<endl; }
void POSSIBLE(bool a){ cout<<(a?"POSSIBLE":"IMPOSSIBLE")<<endl; }
template<class T>auto min(const T& a){ return *min_element(all(a)); }
template<class T>auto max(const T& a){ return *max_element(all(a)); }
template<class T,class F>void print(pair<T,F> a){cout<<a.fi<<" "<<a.se<<endl;}
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0;}
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0;}
template<class T> void ifmin(T t,T u){if(t>u){cout<<-1<<endl;}else{cout<<t<<endl;}}
template<class T> void ifmax(T t,T u){if(t>u){cout<<-1<<endl;}else{cout<<t<<endl;}}
ll fastgcd(ll u,ll v){ll shl=0;while(u&&v&&u!=v){bool eu=!(u&1);bool ev=!(v&1);if(eu&&ev){++shl;u>>=1;v>>=1;}else if(eu&&!ev){u>>=1;}else if(!eu&&ev){v>>=1;}else if(u>=v){u=(u-v)>>1;}else{ll tmp=u;u=(v-u)>>1;v=tmp;}}return !u?v<<shl:u<<shl;}
ll modPow(ll a, ll n, ll mod) { if(mod==1) return 0;ll ret = 1; ll p = a % mod; while (n) { if (n & 1) ret = ret * p % mod; p = p * p % mod; n >>= 1; } return ret; }
vector<ll> divisor(ll x){ vector<ll> ans; for(ll i = 1; i * i <= x; i++){ if(x % i == 0) {ans.push_back(i); if(i*i!=x){ ans.push_back(x / ans[i]);}}}sor(ans); return ans; }
ll pop(ll x){return __builtin_popcountll(x);}
ll poplong(ll x){ll y=-1;while(x){x/=2;y++;}return y;}
P hyou(P a){ll x=fastgcd(abs(a.fi),abs(a.se));a.fi/=x;a.se/=x;if(a.se<0){a.fi*=-1;a.se*=-1;}return a;}
P Pplus(P a,P b){ return hyou({a.fi*b.se+b.fi*a.se,a.se*b.se});}
P Ptimes(P a,ll b){ return hyou({a.fi*b,a.se});}
P Ptimes(P a,P b){ return hyou({a.fi*b.fi,a.se*b.se});}
P Pminus(P a,P b){ return hyou({a.fi*b.se-b.fi*a.se,a.se*b.se});}
P Pgyaku(P a){ return hyou({a.se,a.fi});}
template<class T>
struct Sum{
  vector<T> data;
  Sum(const vector<T>& v):data(v.size()+1){
    for(ll i=0;i<v.size();i++) data[i+1]=data[i]+v[i];
  }
  T get(ll l,ll r) const {
    return data[r]-data[l];
  }
};
template<class T>
struct Sum2{
  vector<vector<T>> data;
  Sum2(const vector<vector<T>> &v):data(v.size()+1,vector<T>(v[0].size()+1)){
    for(int i=0;i<v.size();i++) for(int j=0;j<v[i].size();j++) data[i+1][j+1]=data[i][j+1]+v[i][j];
    for(int i=0;i<v.size();i++) for(int j=0;j<v[i].size();j++) data[i+1][j+1]+=data[i+1][j];
  }
  T get(ll x1,ll y1,ll x2,ll y2) const {
    return data[x2][y2]+data[x1][y1]-data[x1][y2]-data[x2][y1];
  }
};

void cincout(){
  ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
  cout<< fixed << setprecision(15);
}
using mint = modint998244353;
ll Memo[1000000],seen[1000000];
ll sum(ll x,vector<ll> base){
  seen[x]=1;
  ll res=0;
  ll now=1;
  for(int i=0;i<base.size()-1;i++){
    now*=base[i];
    res+=x/now;
  }
  return res%int(base.size());
}
void _ntt(vector<mint> &a,ll sign){
  if(sign==1){
    atcoder::internal::butterfly(a);
  }else {
    atcoder::internal::butterfly_inv(a);
  }
}
vector<vector<mint>> _twofft(vector<vector<mint>> a,vector<vector<mint>> b){
  int n=a.size();
  int m=a[0].size();
  int p=1;
  while(p<m*2) p*=2;
  m=p;
  for(int i=0;i<n;i++){
    a[i].resize(m);
    b[i].resize(m);
    _ntt(a[i],1);
    _ntt(b[i],1);
  }
  vector<vector<mint>> c(n,vector<mint>(m));
  for(int i=0;i<n;i++){
    for(int j=0;i+j<n;j++){
      for(int k=0;k<m;k++){
        c[(i+j)][k]+=a[i][k]*b[j][k];
      }
    }
  }
  for(int i=0;i<n;i++){
    for(int j=n-i;j<n;j++){
      for(int k=0;k<m;k++){
        c[(i+j-n)][k]+=a[i][k]*b[j][k];
      }
    }
  }
  mint u=mint(1)/mint(p);
  for(int i=0;i<n;i++){
    _ntt(c[i],-1);
    for(int j=0;j<m;j++) c[i][j]*=u;
  }
  return c;
}
vector<mint> twofft(vector<mint> a,vector<mint> b,vector<ll> base,ll X=-1){
  ll n=a.size();
  if(X!=-1) n=X;
  ll k=base.size();
  vector<vector<mint>> c(k,vector<mint>(n));
  vector<vector<mint>> d(k,vector<mint>(n));
  for(int i=0;i<n;i++){
    c[sum(i,base)%(k)][i]+=a[i];
    d[sum(i,base)%(k)][i]+=b[i];
  }
  c=_twofft(c,d);
  vector<mint> res(n);
  for(int i=0;i<n;i++){
    ll p=sum(i,base)%(k);
    while(p<int(c.size())){
      res[i]+=c[p][i];
      p+=k;
    }
  }
  return res;
}
vector<mint> multiinv(vector<mint> f,vector<ll> base,ll X=-1){
  ll n=f.size();
  ll k=base.size();
  if(X==-1){
    X=1000000;
  }
  vector<mint> g={mint(1)/mint(f[0])};
  vector<mint> f2,g2;
  for(int d=1;d<min(n,X);d*=2){
    f2.resize(2*d);
    g2.resize(2*d);
    for(int i=0;i<d;i++){
      g2[i]=-g[i];
    }
    for(int i=0;i<min(int(f.size()),2*d);i++){
      f2[i]=f[i];
    }
    f2=twofft(f2,g2,base,2*d);
    f2[0]+=2;
    f2=twofft(f2,g2,base,2*d);
    for(int i=0;i<2*d;i++) f2[i]*=-1;
    g=f2;
  }
  g.resize(min(n,X));
  return g;
}
vector<vector<mint>> station(vector<mint> f,vector<ll> base){
  ll n=f.size();
  ll k=base.size();
  vector<vector<mint>> f2(k,vector<mint>(n));
  for(int i=0;i<n;i++) f2[sum(i,base)%k][i]+=f[i];
  return f2;
}
vector<mint> diff(vector<mint> f){
  for(int i=0;i<int(f.size());i++) f[i]*=i;
  return f;
}
vector<mint> Inv;
vector<mint> integ(vector<mint> f){
  ll n=f.size();
  if(n>Inv.size()){
    ll x=Inv.size();
    Inv.resize(n);
    ll Mod=mint::mod();
    if(x<2) Inv[1]=1;
    for(int i=max(2ll,x);i<n;i++){
      Inv[i]=-Inv[Mod%i]*(Mod/i);
    }
  }
  for(int i=0;i<int(f.size());i++){
    f[i]*=Inv[i];
  }
  return f;
}
vector<mint> multilog(vector<mint> f,vector<ll> base,ll X=-1){
  ll n=f.size();
  ll k=base.size();
  auto g=f;
  f=diff(f);
  if(X==-1){
    g=multiinv(g,base);
  }
  else{
    g=multiinv(g,base,X);
  }
  if(X==-1){
    vector<mint> res=twofft(f,g,base);
    res=integ(res);
    return res;
  }
  else{
    vector<mint> res=twofft(f,g,base,X);
    res=integ(res);
    return res;
  }
}
vector<mint> multiexp(vector<mint> f,vector<ll> base){
  ll n=f.size();
  ll k=base.size();
  if(base.size()==0){
    return {mint(1)};
  }
  else{
    vector<mint> g={mint(1)};
    for(int d=1;d<n;d*=2){
      vector<mint> f2(2*d);
      vector<mint> g2(2*d);
      for(int i=0;i<min(int(f.size()),2*d);i++) f2[i]=f[i];
      f2[0]++;
      for(int i=0;i<d;i++) g2[i]=g[i];
      g2=multilog(g2,base,2*d);
      for(int i=0;i<2*d;i++) f2[i]-=g2[i];
      vector<mint> g3(2*d);
      for(int i=0;i<d;i++) g3[i]=g[i];
      f2=twofft(f2,g3,base,2*d);
      g=f2;
    }
    g.resize(n);
    return g;
  }
}
//次数がずっと同じなら一番上の sum(i,j) のメモ化をした方が早い
constexpr ll MAX = 200010;
ll fac[MAX],finv[MAX],inv[MAX];
void COMinit(){
  fac[0]=fac[1]=1;
  finv[0]=finv[1]=1;
  inv[1]=1;
  for(int i=2;i<MAX;i++){
    fac[i]=fac[i-1]*i%mod;
    inv[i]=mod-inv[mod%i]*(mod/i)%mod;
    finv[i]=finv[i-1]*inv[i]%mod;
  }
}
ll binom(ll n,ll k){
  if(n<k) return 0;
  if(n<0||k<0) return 0;
  return fac[n]*(finv[k]*finv[n-k]%mod)%mod;
}
ll HOM(ll n,ll k){
  if(n==0&&k==0) return 1;
  return binom(n+k-1,k);
}
ll POM(ll n,ll k){
  if(n<k) return 0;
  return fac[n]*finv[n-k]%mod;
}
int main() {
  COMinit();
  cincout();
  ll n,m;
  cin>>n>>m;
  vector<mint> dp((n+1)*(n+1));
  dp[1]=1;
  for(int i=2;i<=n;i++){
    dp[i+(i-1)*(n+1)]=mint(fac[i])/mint(2)*finv[i];
  }
  for(int i=5;i<=n;i++){
    dp[i+i*(n+1)]=mint(fac[i-1])/mint(2)*finv[i];
  }
  dp=multiexp(dp,{n+1,n+1});
  if(n*(n-1)/2-m>n){
    cout<<0<<endl;
    return 0;
  }
  cout<<(dp[n+(n*(n-1)/2-m)*(n+1)]*fac[n]).val()<<endl;
}