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#include <iostream>

const int MAX_S = 2000;

long long digit_square_sum(long long num) {
	long long res = 0;
	while(num != 0) {
		res += (num % 10) * (num % 10);
		num /= 10;
	}
	
	return res;
}

bool check(long long k, long long n) {
	long long s = digit_square_sum(n);
	if(n % s != 0) return false;
	return k == n / s;
}

int main() {
	long long k, a, b;
	std::cin >> k >> a >> b;

	int result = 0;

	for(long long i = 1; i <= MAX_S && i * k <= b; i++) {
		if(a <= i * k && check(k, i * k)) result ++;
	}

	std::cout << result << std::endl;
}