#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 1e5;
const int LIM = 300;
const int MOD = 1e9 + 7;
int d[MAX_N + 1], x[MAX_N + 1], dp[MAX_N + 1], sum[LIM + 1][LIM];
vector<int> events[MAX_N + 1];
int main() {
int n;
cin >> n;
for ( int i = 1; i <= n; i++ )
cin >> d[i] >> x[i];
dp[1] = 1;
for ( int i = 1; i <= n; i++ ) {
for ( int j = 1; j <= LIM; j++ )
dp[i] = (dp[i] + sum[j][i % j]) % MOD;
if ( d[i] > LIM ) {
for ( int j = i + d[i]; j <= n && j <= i + (long long)x[i] * d[i]; j += d[i] )
dp[j] = (dp[j] + dp[i]) % MOD;
} else if ( d[i] != 0 ) {
sum[d[i]][i % d[i]] = (sum[d[i]][i % d[i]] + dp[i]) % MOD;
if ( i + (long long)x[i] * d[i] <= n )
events[i + x[i] * d[i]].push_back( i );
}
for ( int j: events[i] )
sum[d[j]][j % d[j]] = (sum[d[j]][j % d[j]] - dp[j] + MOD) % MOD;
}
int ans = 0;
for ( int i = 1; i <= n; i++ )
ans = (ans + dp[i]) % MOD;
cout << ans;
return 0;
}
