def primes(n):
    is_prime = [True] * (n + 1)
    is_prime[0] = False
    is_prime[1] = False
    for i in range(2, int(n**0.5) + 1):
        if not is_prime[i]:
            continue
        for j in range(i * 2, n + 1, i):
            is_prime[j] = False
    return [i for i in range(n + 1) if is_prime[i]]

n = int(input())
if n == 0:
    print(-1)
    exit(0)
ans = []
p = primes(1000000)
p.reverse()
idx = 0
for ps in p:
    if (ps + 1) ^ n < n:
        n ^= ps + 1
        ans.append(ps)
if n == 1:
    ans.append(1)
print(len(ans))
print(*ans)