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#include <iostream>
using namespace std;

int f(long long n = 0)
{
    int digit = 0, sum = 0;
    do
    {
        digit = n % 10;
        sum += digit * digit;
        n /= 10;
    }
    while(n != 0);

    return sum;
}

int main()
{
    long long k, a, b;
    int quantity = 0;
    cin >> k >> a >> b;

    for(long long i = a; i <= b; i++)
    {
        if(k * f(i) == i)
            ++quantity;
    }
    cout << quantity << endl;

    return 0;
}