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#include <bits/stdc++.h>

using namespace std;

const int MAX_SUM = 81 * 18;

int sumOfDigitsSquares(long long x) {
    int ret = 0;
    while (x) {
        ret += (x % 10) * (x % 10);
        x /= 10;
    }
    return ret;
}

int main() {
    long long k, a, b;
    scanf("%lld %lld %lld", &k, &a, &b);
    
    int ans = 0;
    
    for (int i = 0; i <= MAX_SUM; i++) {
        if (k * i > b) {
            break;
        }
        if (a <= k * i && k * i <= b && sumOfDigitsSquares(k * i) == i) {
            ans++;
        }
    }
    
    printf("%d\n", ans);
    return 0;
}