/*
* Author: Nonoze
* Created: Sunday 05/05/2024
*/
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T> using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long ll;
#define int long long
#ifndef _IN_LOCAL
#define dbg(...) ;
#endif
#define sz(x) (int)(x.size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define endl '\n'
#define endlfl '\n' << flush
#define quit(x) {cout << x << endl; return;}
#define cmin(a, b) a = min(a, b)
#define cmax(a, b) a = max(a, b)
const int inf = numeric_limits<int>::max() / 4;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MOD = 1e9+7, LOG=25;
int mod(int x) {
return ((x%MOD)+MOD)%MOD;
}
void solve();
signed main() {
ios::sync_with_stdio(0);
cin.tie(0);
int tt=1;
// cin >> tt;
while(tt--) solve();
return 0;
}
int n, m, q;
const int k=320;
vector<int> a, d, sz, idx;
int sum[k][k][k], block[k][k];
void build() {
sz.resize(k), idx.resize(k);
for (int i=0; i<n; i++) {
if (!sz[i/k]) idx[i/k]=i;
sz[i/k]++;
}
}
int get(int pos) {
int bpos=pos%k;
int ans=block[pos/k][bpos];
if (!pos) ans=mod(ans+1);
for (int i=1; i<k; i++) {
ans+=sum[pos/k][i][bpos%i];
mod(ans);
}
return mod(ans);
}
int solveboth(int nb, int pos, int start, int end) {
for (int i=start+1; i<k && idx[i]<=end; i++) {
int l=idx[i], r=l+sz[i]-1;
int empl = (idx[i] - pos) / d[pos] + ((idx[i] - pos) % d[pos] != 0);
empl *= d[pos];
empl += pos;
// if (empl<l) empl+=d[pos];
if (empl>r) continue;
int bpos=empl%k;
if (r>end || d[pos]>=k) {
for (int j=bpos; j<k && idx[i]+j<=end; j+=d[pos]) {
block[i][j]+=nb;
mod(block[i][j]);
}
continue;
}
sum[i][d[pos]][bpos%d[pos]]+=nb;
mod(sum[i][d[pos]][bpos%d[pos]]);
}
return nb;
}
int update(int pos) {
if (!d[pos]) return get(pos);
int start=pos/k, end=min(n-1, pos+d[pos]*a[pos]);
int nb=get(pos);
for (int i=pos+d[pos]; i<k*start+k && i<=end; i+=d[pos]) {
block[i/k][i%k]+=nb;
mod(block[i/k][i%k]);
}
return solveboth(nb, pos, start, end);
}
void solve() {
cin >> n;
a.resize(n), d.resize(n);
for (int i=0; i<n; i++) cin >> d[i] >> a[i];
build();
int ans=0;
for (int i=0; i<n; i++) ans=mod(ans+update(i));
cout << ans << endl;
}
