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#include <iostream>
#include <set>
#include <vector>
#include <cmath>

using namespace std;

#define log if (false) cerr
typedef long long ll;
typedef unsigned long long ull;

const ull INF = 1000000000000000000ull;


int numberOfDigits(ull x)
{
    int result = 0;
    while (x > 0)
    {
        result++;
        x /= 10;
    }
    return result;
}


set<ull> computeFns(ull maxPossible)
{
    int maxPosition = numberOfDigits(maxPossible);
    set<ull> fns;
    fns.insert(0);
    for (int pos = 1; pos <= maxPosition; pos++)
    {
        set<int> newFns;
        for (int digit = 1; digit <= 9; digit++)
        {
            for (auto fn : fns)
            {
                newFns.insert(fn + digit * digit);
            }
        }
        fns.insert(newFns.begin(), newFns.end());
    }

    fns.erase(0);
    return fns;
}


ull fun(ull n)
{
    ull result = 0;
    while (n > 0)
    {
        result += (n % 10) * (n % 10);
        n /= 10;
    }
    return result;
}

int solve(const set<ull>& fns, ull a, ull b, ull k)
{
    ull maxFn = b / k;
    ull minFn = a / k;
    int count = 0;
    for (auto fn : fns)
    {
        if (fn < minFn)
        {
            continue;
        }
        if (fn > maxFn)
        {
            break;
        }
        ull n = k * fn;
        if (n >= a && n <= b && fun(n) == fn)
        {
            count++;
            log << n << endl;
        }
    }
    return count;
}


int main()
{
    ull a, b, k;
    a = 4080; b = 7905; k = 51;
    // a = 1; b = INF; k = INF / 200;
    cin >> k >> a >> b;
    set<ull> fns = computeFns(b);
    cout << solve(fns, a, b, k);
    return 0;
}