# My Third attempt was succeded
# My First Attempt

L = []
n = int(input(""))
if n >= 2 and n <= 10**5:
    for i in range(2, n+1):
        for j in range(2, n+1):
            k = i**j
            if k not in L:
                L.append(k)
            else:
                pass
    print(len(L))
else:
    pass
# Failed

# My Second Attempt

N = int(input())
L = [True] * (N+1)
res = 0
for i in range(2, N+1):
    if L[i]:
        power = 2
        res = []
        while i**power <= N:
            L[i**power] = False
            res += [n for n in range(2*power, N * power+1, power) if n>N]
            power+=1
        res += len(set(res))+(N-1)
        
print(res)
# Failed

# My Final Attempt

def dist_term(n: int) -> int:
    count = 0
    test = [0]*(n+1)
    for i in range(2, n+1):
        if test[i]: continue;
        combined = set()
        po = 2
        while (i**po <= n):
            test[i**po] = True
            s = set([j*po for j in range(2, n+1) if j*po > n])
            combined.update(s)
            po += 1
        count += len(combined) + n-1
    return count
            
print(dist_term(int(input())))