friendly numbers

k = int(input())

res = set()

def sum_divisors(n):
    i = 2
    res = 1
    while i <= n**0.5:
        if n % i == 0:
            res += i
            if i != n**0.5:
                res += n // i
        i += 1
    return res

for num in range(1, k+1):
    cand = sum_divisors(num)

    if cand != num and cand <= k and sum_divisors(cand) == num:
        res.add((min(num, cand), max(num, cand)))

for pair in list(res):
    print(f'{pair[0]} {pair[1]}')