#include<bits/stdc++.h>
using namespace std;
typedef unsigned long long ll;
#define MAX 10000
#define all(v) v.begin(),v.end()
ll N=5*1e6+2,m;
vector<bool>isprime(N);
vector<ll>phi;
vector<ll>prime;

void seive()
{
    ll i,n=N,j;
    isprime[1]=1;
    isprime[0]=1;

    for(i=4; i<=n; i+=2)
        isprime[i]=1;

    for(i=3; i*i<=n; i+=2)
    {
        if(isprime[i]==0)
            for(j=i*i; j<=n; j+=i)
                isprime[j]=1;
    }
    for(i=0; i<=n; i++)
    {
        if(isprime[i]==0)
            prime.push_back(i);
    }
}

void solve()
{
    ll i,j;
    for(i=0; i<N; i++)
        phi.push_back(i);
    for(i=0; i<prime.size(); i++)
    {
        for(j=prime[i]; j<N; j+=prime[i])
        {
            phi[j]*=(prime[i]-1);
            phi[j]/=prime[i];
        }
    }
}

int main()
{
    seive();
    solve();
   // freopen("input.txt","r",stdin);
    // freopen("output.txt","w",stdout);
    ll test,t,i;
    vector<ll>a(N+8,0);
    for(i=2; i<N; i++)
        a[i]=phi[i]*phi[i]+a[i-1];
    scanf("%llu",&test);
    for(t=1; t<=test; t++)
    {
        ll a1,b;
        scanf("%llu %llu",&a1,&b);
        a1--;
        printf("Case %llu: %llu\n",t,a[b]-a[a1]);
    }
}