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#include <cstdio>
#include <cmath>

using std::pow;
using std::scanf;
using std::printf;

int main()
{
  const long long int maxNum = pow(10, 18);
  const int maxSum = (9*9) * 18;

  long long int a;
  long long int b;
  long long int k;

  scanf("%lld%lld%lld", &k, &a, &b);

  int correctNumbers = 0;
  for (int expectedSum = 1; expectedSum <= maxSum; expectedSum++)
  {
    if (maxNum / k < expectedSum)
      break;

    long long int suspectNum = expectedSum * k;
    if (suspectNum < a)
      continue;
    if (suspectNum > b)
      break;

    int suspectSum = 0;
    while (suspectNum)
    {
      int digit = suspectNum % 10;
      suspectSum += digit * digit;
      suspectNum /= 10;
    }
    
    if (suspectSum == expectedSum)
      correctNumbers++;
  }

  printf("%d\n", correctNumbers);

  return 0;
}