#include<bits/stdc++.h>
#define pb push_back
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in(a) int a; cin>>a
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out(a) cout<<a<<'\n'
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define vout(v) for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
const int mxn = 1e5 + 5;
int tree[mxn * 4];
int n;
void update(int k, int x){
k += n;
tree[k] += x;
tree[k] %= leg;
for(k/=2; k>=1; k/=2){
tree[k] = tree[k*2] + tree[k*2 + 1];
tree[k] %= leg;
}
}
void rangeupdate(int l, int r, int x){
if(l <= r){
update(l, x);
if(r != n-1)update(r+1, -x);
}
}
int quer(int l, int r){
l += n;
r += n;
int ret = 0;
while(l <= r){
if(l % 2 == 1)ret += tree[l++];
if(r % 2 == 0)ret += tree[r--];
l/=2;
r/=2;
}
return ret;
}
int pointquer(int x){
return quer(0, x);
}
signed main(){
ios::sync_with_stdio(false);
cin.tie(NULL);
//ifstream cin(".in");
//ofstream cout(".out");
cin>>n;
if(n <= 1e4){
vvi adj(n);
vi dp(n);
dp[0] = 1;
f0r(i,n){
in2(d,x);
if(d != 0){
for(int j = i + d; j <= min(n-1, i + d * x); j += d){
adj[j].pb(i);
}
}
}
FOR(i, 1, n){
for(auto u : adj[i]){
dp[i] += dp[u];
dp[i] %= leg;
}
}
//vout(dp);
int sum = 0;
f0r(i, n){
sum += dp[i];
sum %= leg;
}
out(sum);
}
else{
rangeupdate(0, 0, 1);
f0r(i,n){
in2(d,x);
//add dp[i] to range [i+1, min(i+x, n-1)]
rangeupdate(i+1, min(i+x, n-1), pointquer(i));
//out3(i+1, min(i+x, n-1), pointquer(i));
}
int sum = 0;
f0r(i,n){
sum += pointquer(i);
//cout<<pointquer(i)<<' ';
sum %= leg;
}
//out("");
out(sum);
}
}
