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#include <iostream>
#include <vector>
#include <set>
using namespace std;

long long f(long long n)
{
  long long sqrtSum = 0;
  while(n > 0)
  {
    int digit = n % 10;
    sqrtSum += digit * digit;
    n /= 10;
  }
  return sqrtSum;
}

const long long MAX_SUM = 1458; //9 * 9 * 18

int main()
{
  ios_base::sync_with_stdio(false);
  long long k, a, b;
  cin >> k >> a >> b;
  int count = 0;
  for(long long i = 0; i <= MAX_SUM; ++i)
  {
    unsigned long long n = i * k;
    if(n > b)
      break;
    if(n < a)
      continue;
    if(f(n) * k == n)
      count++;
  }
  cout << count << endl;
  return 0;
}