#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 4000000000000000001



int main(){
	
	long long n,m;
	cin>>n>>m;
	
	long long s = n * (n+1) / 2;
	if(s <=m)cout<<"Yes"<<endl;
	else cout<<"No"<<endl;
	
	return 0;
}