N = int(input())
P = list(range(N+1))
P[0] = -1
P[1] = -1
for i in range(2,N+1):
    if i*i>N:break
    for j in range(i*i,N+1,i):
        P[j] = P[i]
Q = []
for i in range(2,N+1):
    if P[i]==i:
        Q.append(i)
S = []
for r in Q:
    if r**2>2*N:break
    S.append(r**2)
ans = 0
for z in S:
    for p in Q:
        if N>=z-p>0 and P[z-p]==z-p:
            ans += 1
print(ans)