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#include <cstdio>
using namespace std;

typedef long long LL;

LL sq(LL n) { return n*n; }
int f(LL n) { return n ? f(n/10) + sq(n%10) : 0; }

int main() {
  LL k, a, b;
  scanf("%lld %lld %lld", &k, &a, &b);
  int res = 0;
  for (LL i=1;i <= 18*81 && k*i <= b;i++)
  {
    LL n = k*i;
    res += n >= a && f(n) == i;
  }
  printf("%d\n", res);
  return 0;
}