#include <bits/stdc++.h>
#define int long long
using namespace std;
using ll = long long;
const int mod = 1e9 + 7;
const int maxn = 1e5 + 5;
ll dp[maxn+5], pref[325][maxn+5], rem[325][maxn+5];
int32_t main() {
ios_base::sync_with_stdio(false);
cout.tie(0); cin.tie(0);
int n, mx = 0, mx2=0;
cin >> n;
int B = sqrt(n);
vector<int> d(n+1), x(n+1);
for(int i=0; i<n; i++) cin >> d[i] >> x[i];
for(int i=0; i<n; i++) mx = max(mx, d[i]);
for(int i=0; i<n; i++) mx2 = max(mx2, x[i]);
dp[0] = 1;
for(int i=0; i<n; i++) {
for(int j=1; j<=B; j++) {
pref[j][i%j] = (pref[j][i%j] - rem[j][i] + mod) % mod;
}
for(int j=1; j<=B; j++) {
dp[i] += pref[j][i%j];
dp[i] %= mod;
}
if(d[i] == 0) continue;
if(d[i] > B) {
for(int j=i+d[i]; j<=min((ll)n, (ll)i+x[i]*d[i]); j+=d[i]) dp[j] = (dp[j] + dp[i]) % mod;
} else {
pref[d[i]][i%d[i]] += dp[i];
pref[d[i]][i%d[i]] %= mod;
if((ll)i + (ll)(x[i]+1)*d[i] <= n) {
rem[d[i]][i+(x[i]+1)*d[i]] += dp[i];
rem[d[i]][i+(x[i]+1)*d[i]] %= mod;
}
}
}
ll ans = 0;
for(int i=0; i<n; i++) ans = (ans + dp[i]) % mod;
cout << ans << '\n';
return 0;
}
