#include <bits/stdc++.h>
#define int long long
#define double long double
#define pdi pair<double,pair<pair<int,pair<int,int>>,int>>
#define mid ((l+r)>>1)
using namespace std;
const int mod=998244353;
double pw[17][1000005];
int mpw[17][1000005],k=0;
int pl[1000005];
int pre[1000005];
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	for(int i=2;i<=16;i++){
		pw[i][0]=1;
		mpw[i][0]=1;
		for(int j=1;j<=1000000;j++) pw[i][j]=pw[i][j-1]*i,mpw[i][j]=mpw[i][j-1]*i%mod;
	}
	priority_queue<pdi,vector<pdi>,greater<pdi>> pq;
	for(int i=2;i<=16;i++){
		for(int j=1;j<i;j++){
			pq.push(make_pair(pw[i][0]*j,make_pair(make_pair(i,make_pair(j,0)),mpw[i][0]*j%mod)));
		}
	}
	while(k<=1000000){
		auto f=pq.top(); pq.pop();
		auto t=f;
		// cout<<f.second.first.first<<" "<<f.second.first.second.first<<" "<<f.second.first.second.second<<" "<<t.second.second<<"\n";
		t.second.first.second.second++;
		t.first+=pw[t.second.first.first][t.second.first.second.second]*t.second.first.second.first;
		(t.second.second+=mpw[t.second.first.first][t.second.first.second.second]*t.second.first.second.first)%=mod;
		pq.push(t);
		if(f.second.second!=pl[k]){
			pl[++k]=f.second.second;
		}
	}
	for(int i=1;i<=1000000;i++) (pl[i]+=pl[i-1])%=mod;
	int t; cin>>t;
	while(t--){
		int l,r; cin>>l>>r;
		cout<<(pl[r]+mod-pl[l-1])%mod<<"\n";
	}
	return 0;
}