#danglam228

#include <bits/stdc++.h>
using namespace std;
int t;
const int N = 1e6 + 5;
vector<bool> s(N, true);
vector<int> a;
bool tt(int num) {
    while (num > 0) {
        if (num % 10 != 5) return false;
        num /= 10;
    }
    return true;
}
void sg() {
    s[0] = s[1] = false;
    for (int i = 2; i * i < N; i++) {
        if (s[i]) {
            for (int j = i * i; j < N; j += i) {
                s[j] = false;
            }
        }
    }
    for (int i = 2; i < N; i++) {
        if (s[i] && tt(i)) {
            a.push_back(i);
        }
    }
}
int main() {
    sg();
    cin >> t;
    while (t--) {
        int l, r;
        cin >> l >> r;
        cout << upper_bound(a.begin(), a.end(), r) - lower_bound(a.begin(), a.end(), l) << '\n';
    }
    return 0;
}