#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#define pb push_back
#define F first
#define S second
#define all(a) a.begin(),a.end()
#define pii pair <int,int>
#define PII pair<pii , pii>
#define ld long double
#define int long long
#define sz(v) (int)v.size()
#define rep(i , a , b) for(int i=a;i <= b;i++)
#define per(i, a , b) for(int i=a;i >= b;i--)
using namespace std ;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxn = 2e5+10 , N = 1e5 +1 , lg = 20 , maxq = 202 , sq = 333 , inf = 1e18 , maxk = 2022 , mod =1e9 + 7;
int s[maxn][sq+2] , d[maxn] , x[maxn] , ans[maxn] ;
vector <int> vec[maxn] ;
signed main(){
ios_base::sync_with_stdio(false); cin.tie(0);
int n ;
cin >> n ;
rep(i , 1, n){
cin >> d[i] >> x[i] ;
if(d[i] <= sq && i+d[i]*(x[i] + 1) <= n){
vec[i+d[i]*(x[i]+1)].pb(i);
}
}
per(i , n , 1){
if(d[i] <= sq){
ans[i] = (ans[i] + 1 + s[i+d[i]][d[i]] )%mod ;
}else{
ans[i] =1 ;
for(int j = 1 ; j <= x[i] && i+j*d[i] <= n ; j++){
ans[i] = (ans[i] + ans[i+j*d[i]])%mod ;
}
}
rep(j ,1 , sq){
s[i][j] = (ans[i]+ s[i+j][j])%mod ;
}
for(int x : vec[i]){
ans[x] = (ans[x] - s[i][d[x]] + mod)%mod ;
}
}
cout << ans[1] << "\n" ;
}
/*
*/
