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#include <bits/stdc++.h>

using namespace std;

typedef unsigned long long uLL;

int digits_of(uLL x)
{
    int i = 1;
    for(uLL pow10 = 10; x >= pow10; pow10 *= 10, ++i);
    return i;
}

int sum_of_squared_digits(uLL num)
{
    int sum = 0;
    while(num > 0)
    {
        int digit = num % 10;
        sum += digit*digit;
        num /= 10;
    }
    return sum;
}

vector<int> squares;

void gen_sqr(int digit, int free, int sum)
{
    for(int i = 0; i <= free; ++i, sum += digit*digit)
        if(digit == 9)
            squares.push_back(sum);
        else
            gen_sqr(digit+1, free-i, sum);
}

void generate_squares(int digits)
{
    gen_sqr(0, digits, 0);
}


int main()
{
    uLL k, a, b;
    cin >> k >> a >> b;
    int  digits_b = digits_of(b);
    generate_squares(digits_b);
    cerr << squares.size() << endl;
    sort(squares.begin(), squares.end());
    squares.resize(unique(squares.begin(), squares.end()) - squares.begin());
    uLL res = 0;
    for(int sum : squares)
    {
        uLL num = k * sum;
        if(num >= k && a <= num && num <= b && sum == sum_of_squared_digits(num))
            ++res;
    }
    cout << res << endl;
}