#include<stdio.h>

int sax(int n) {
    return n * (n + 1) / 2;
}
	
int main(){
	int T,sum;
	scanf("%d",&T);
	int a[T],b[T];
	for(int i=0;i<T;i++){
		scanf("%d%d",&a[i],&b[i]);
		if(a[i]<sax(b[i])){
		printf("No");
		return 0;
		}
	}
	printf("Yes");
	return 0;
}