// yukicoder: No.843 Triple Primes
// 2019.6.29 bal4u

#include <stdio.h>

#define MAX  1000000
#define SQRT 1000
char nop[MAX+5] = { 1,1,0,0,1 };			// zero: if prime 

void sieve() {
	int i, j;
	for (i = 3; i <= SQRT; i += 2) if (!nop[i]) {
		for (j = i * i; j <= MAX; j += i) nop[j] = 1;
	}
}

int main()
{
	int i, k, N, ans;

	sieve();
	scanf("%d", &N);
	
	ans = 0;
	if (N > 1) {
		i = 3; while (1) {
			if (!nop[i]) {
				if ((k = i*i-2) > N) break;
				if (!nop[k]) ans++;
			}
			i += 2;
		}
		ans <<= 1, ans++;
	}
	printf("%d\n", ans);
	return 0;
}