#include <bits/stdc++.h>
using namespace std;
const int maxn = 100005;
const int BLOCK_SIZE = 355;
const int mod = 1e9 + 7;
int n;
int d[maxn], x[maxn];
int dp[maxn];
int pref[maxn];
int prefSmall[BLOCK_SIZE][BLOCK_SIZE];
vector<tuple<int, int, int>> toRemove[maxn];
void fastIO()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
int main()
{
fastIO();
cin >> n;
for (int i = 1; i <= n; ++i)
{
cin >> d[i] >> x[i];
}
int big = sqrt(n);
int ans = 0;
for (int i = 1; i <= n; ++i)
{
for (auto [small, rem, value] : toRemove[i])
{
prefSmall[small][rem] -= value;
if (prefSmall[small][rem] < 0) prefSmall[small][rem] += mod;
}
if (i == 1)
{
dp[i] = 1;
}
else
{
for (int small = 1; small < big; ++small)
{
dp[i] += prefSmall[small][i % small];
if (dp[i] >= mod) dp[i] -= mod;
}
}
if (d[i] >= big && d[i] != 0)
{
for (int j = i + d[i]; j <= n && x[i] > 0; j += d[i])
{
--x[i];
dp[j] += dp[i];
if (dp[j] >= mod) dp[j] -= mod;
}
}
else if (d[i] != 0)
{
prefSmall[d[i]][i % d[i]] += dp[i];
if (prefSmall[d[i]][i % d[i]] >= mod) prefSmall[d[i]][i % d[i]] -= mod;
toRemove[min(1LL * n + 1LL, i + (1LL * x[i]) * (1LL * d[i]) + 1LL)].push_back({d[i], i % d[i], dp[i]});
}
ans += dp[i];
if (ans >= mod) ans -= mod;
//cout << i << " :: " << dp[i] << endl;
}
cout << ans << endl;
return 0;
}
/*
5
1 3
1 1
0 4
1 2
1 2
5
1 3
1 1
1 2
1 2
1 2
2 :: 1
3 :: 2
4 :: 3
5 :: 5
12
3 1000000000
5 1000000000
2 1000000000
7 1000000000
4 1000000000
1 1000000000
1 1000000000
5 1000000000
2 1000000000
1 1000000000
1 1000000000
3 1000000000
here 2 :: 0
here 3 :: 0
here 4 :: 1
here 5 :: 0
here 6 :: 0
here 7 :: 1
here 8 :: 1
here 9 :: 1
here 10 :: 2
here 11 :: 5
here 12 :: 8
*/
