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#include <iostream>

int RNC(int x, int(&k)[18]);
int DL(int x);
int KW(int x, int y);

int f(int n);

using namespace std;

int main(){
	int n=0;
	unsigned long long int a, b, k;
	cin >> k;
	cin >> a;
	cin >> b;

	for (int i = a; i <= b; i++){
		if (k * f(i) == i){
			n += 1;
		}
	}

	cout << n;
}

int RNC(int x, int(&k)[18]){
	int n;
	int a = 0;

	n = DL(x);

	for (int i = 0; i < n; i++){
		k[i] = (x / KW(10, n - i - 1)) - a;
		a = (a + k[i]) * 10;
	}

	return 0;
}

int DL(int x){
	for (int i = 0;; i += 1){
		if (x > 0){
			x /= 10;
		}
		else{
			return i;
		}
	}
}

int KW(int x, int y){
	int k = 1;

	for (int i = 0; i < y; i++){
		k *= x;
	}

	return k;
}

int f(int n){
	int l[18];
	int k=0;

	RNC(n, l);

	for (int i = 0; i < DL(n); i++){
		k += KW(l[i], 2);
	}

	return k;
}