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#include <stdio.h>
 
int main(void) {
	unsigned long long k, a, b, ans, i;
	scanf("%llu %llu %llu", &k, &a, &b);
	
	const squares[] = { 0, 1, 4, 9, 16, 25, 36, 49, 64, 81 };
 
	ans = 0;
	for(i = a; i <= b; ++i) {
		unsigned long long squares_sum = 0;
		unsigned long long n = i;
		while(n) {
		    squares_sum += squares[n % 10];
		    n /= 10;
		}
		if(squares_sum * k == i) {
			ans += 1;
		}
	}
 
	printf("%llu", ans);
 
	return 0;
}