#include <bits/stdc++.h>
using namespace std;
#define el "\n"
#define FOR(i,a,b) for(int i = (a), _b = (b); i <= _b; i++)
#define FORD(i,a,b) for(int i = (a), _b = (b); i >= _b; i--)
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(),x.end()
#define lg(x) __lg(x)
#define alla(a,n) a+1,a+n+1
#define ll long long
template <class T> bool maxi(T &x, T y) { if(x < y) { x = y ; return true ;} return false;}
template <class T> bool mini(T &x, T y) { if(x > y) { x = y ; return true ;} return false;}
const int sm = 1e9 + 7;
const int N = 1e5 + 2;
#define int ll
int n, x[N], d[N];
void inp()
{
cin >> n;
FOR(i, 1, n) cin >> d[i] >> x[i];
}
/* Try your best
No regrets */
void add(int &x, int y)
{
x += y;
if(x >= sm) x -= sm;
if(x < 0) x += sm;
}
namespace subtask_1
{
int dp[N];
void slv()
{
dp[1] = 1;
FOR(i, 1, n - 1) if(d[i]) {
FOR(t, 1, x[i]) {
int far = i + d[i] * t;
if(far > n) break;
add(dp[far], dp[i]);
}
}
int ans = 0;
FOR(i, 1, n) add(ans, dp[i]);
cout << ans;
}
}
namespace subtask_3
{
bool check_sub()
{
FOR(i, 1, n) if(d[i] > 1) return 0;
return 1;
}
int dp[N];
int st[4 * N], lz[4 * N];
void down(int id)
{
if(lz[id]) {
int val = lz[id];
add(st[id << 1], val); add(st[id << 1 | 1], val);
add(lz[id << 1], val); add(lz[id << 1 | 1], val);
lz[id] = 0;
}
}
void upd(int id, int l, int r, int u, int v, int val)
{
if(r < u || v < l) return;
if(u <= l && r <= v) {
add(st[id], val);
add(lz[id], val);
return;
}
int mid = (r + l) >> 1;
down(id);
upd(id << 1, l, mid, u, v, val);
upd(id << 1 | 1, mid + 1, r, u, v, val);
st[id] = max(st[id << 1], st[id << 1 | 1]);
}
int get(int id, int l, int r, int pos)
{
if(pos > r || pos < l) return 0;
if(l == r) return st[id];
int mid = (r + l) >> 1;
down(id);
return max(get(id << 1, l, mid, pos), get(id << 1 | 1, mid + 1, r, pos));
}
void slv()
{
dp[1] = 1;
upd(1, 1, n, 1, 1, dp[1]);
FOR(i, 1, n) {
dp[i] = get(1, 1, n, i);
upd(1, 1, n, i + 1, min(n, i + x[i]), dp[i]);
}
int ans = 0;
FOR(i, 1, n) add(ans, dp[i]);
// FOR(i, 1, n) cout << dp[i] << " "; cout << el;
cout << ans;
}
}
/* Code slowly, think carefully */
main()
{
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define __Azul__ "task"
if(fopen(__Azul__".inp", "r")) {
freopen(__Azul__".inp", "r", stdin);
freopen(__Azul__".out", "w", stdout);
}
bool qs = 0;
int T = 1;
if(qs) cin >> T;
while(T--) {
inp();
subtask_3::slv();
}
cerr << "\nTime" << 0.001 * clock() << "s "; return 0;
}
