#include <iostream>
#define rep(i, l, n) for (ll i = (l); i < (n); i++)
using namespace std;
using ll = long long;

bool check(ll n, ll p, ll a, ll b) {
	return (p * p < n * (p * a + b) + 1);
}

int main(void) {
	ll n;	cin >> n;

	ll ans = 0;
	rep(a, 0, 10) {
		rep(b, 0, 10) {
			if (a == b) {
				continue;
			}
			ll min_p = max(a, b) + 1;
			if (check(n, min_p, a, b) == false) {
				continue;
			}
			ll ok = min_p, ng = 1000000000ll;
			while (ng - ok > 1) {
				ll p = (ok + ng) >> 1;
				if (check(n, p, a, b)) {
					ok = p;
				}
				else {
					ng = p;
				}
			}
			ans += ok - min_p + 1;
		}
	}

	cout << ans << endl;

	return 0;
}