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#include <cstdio>

#define FMAX (9*9 * 19)


int f(unsigned long long n)
{
  int res = 0;
  while (n)
  {
    int d = n % 10;
    res += (d * d);
    n /= 10;
  }

  return res;
}

int main()
{
  unsigned long long k, a, b;

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

  // k * f(n) = n;
  // f(n) <= FMAX
  // f(n) = k/n
  // k/n <= FMAX

  int res = 0;

  for (int i = 1; i <= FMAX; ++i)
  {
    unsigned long long n = i * k;

    if (n > b)
      break;

    if (n >= a && f(n) == i)
    {
//      printf("< %llu\n", n);
      ++res;
    }
  }

  printf("%d\n", res);
}