isprime = [0, 0] + [1] * (10 ** 6 - 1)

for i in range(2, 10 ** 3 + 1):
    
    if isprime[i]:
        
        for j in range(2 * i, 10 ** 6 + 1, i):
            
            isprime[j] = 0
            
ans = 0

N = int(input())

P = [i for i in range(2, N + 1) if isprime[i]]

from bisect import bisect

for i in range(bisect(P, int((2 * N) ** 0.5))):
    
    for p in P:
        
        if P[i] ** 2 - N <= p < P[i] ** 2 and isprime[P[i] ** 2 - p]:
            
            ans += 1
            

print(ans)