#include <bits/stdc++.h>
using namespace std;

using ll = long long;
#define rep(i, n) for(ll i = 0; i < n; i++)

int main() {
	ll N, M;
	cin >> N >> M;
	string ans = "No";
	if(N * (N + 1) / 2 <= M) ans = "Yes";
	cout << ans << endl;
}