Problem:
Chief Judge's log, stardate 48642.5. We have decided to make a problem from elementary number theory. The problem looks like finding all prime factors of a positive integer, but it is not.  A positive integer whose remainder divided by 7 is either 1 or 6 is called a 7 ** _N_** +{1,6} number. But as it is hard to pronounce, we shall call it a _Monday-Saturday number_.  For Monday-Saturday numbers _a_ and _b_ , we say _a_ is a Monday-Saturday divisor of _b_ if there exists a Monday-Saturday number _x_ such that _a_ _x_ = _b_. It is easy to show that for any Monday-Saturday numbers _a_ and _b_ , it holds that _a_ is a Monday-Saturday divisor of _b_ if and only if _a_ is a divisor of _b_ in the usual sense.  We call a Monday-Saturday number a _Monday-Saturday prime_ if it is greater than 1 and has no Monday-Saturday divisors other than itself and 1. A Monday- Saturday number which is a prime in the usual sense is a Monday-Saturday prime but the converse does not always hold. For example, 27 is a Monday-Saturday prime although it is not a prime in the usual sense. We call a Monday-Saturday prime which is a Monday-Saturday divisor of a Monday-Saturday number _a_ a _Monday-Saturday prime factor_ of _a_. For example, 27 is one of the Monday- Saturday prime factors of 216, since 27 is a Monday-Saturday prime and 216 = 27 × 8 holds.  Any Monday-Saturday number greater than 1 can be expressed as a product of one or more Monday-Saturday primes. The expression is not always unique even if differences in order are ignored. For example, 216 = 6 × 6 × 6 = 8 × 27 holds.  Our contestants should write a program that outputs all Monday-Saturday prime factors of each input Monday-Saturday number.

Incorrect submission (verdict: Wrong Answer):
this_prime_num = [0 for i in range(300001)]

for i in range(300001):
    if i % 7 == 1 or i % 7 == 6:
        this_prime_num[i] = 1
for i in range(2, 300001):
    j = i * 2
    while this_prime_num[i] == 1 and  j < len(this_prime_num):
        #print(j)
        this_prime_num[j] = 0
        j += i


this_primenum_list = []
for i in range(2, len(this_prime_num)):
    if this_prime_num[i]:
        this_primenum_list.append(i)
print(this_primenum_list[:30])
ans_list = []
while True:
    n = int(input())
    if n == 1:
        break
    i = 0
    ans = [n]
    while this_primenum_list[i] <= n:
        #print(i)
        if n % this_primenum_list[i] == 0:
            ans.append(this_primenum_list[i])
        i += 1
        if i >= len(this_primenum_list):
            break
    ans_list.append(ans)

for i in ans_list:
    print(str(i[0]) + ":", end = "")
    for j in i[1:]:
        print("", end = " ")
        print(j, end = "")
    print()


Fixed, accepted submission:
this_prime_num = [0 for i in range(300001)]

for i in range(300001):
    if i % 7 == 1 or i % 7 == 6:
        this_prime_num[i] = 1
for i in range(2, 300001):
    j = i * 2
    while this_prime_num[i] == 1 and  j < len(this_prime_num):
        #print(j)
        this_prime_num[j] = 0
        j += i


this_primenum_list = []
for i in range(2, len(this_prime_num)):
    if this_prime_num[i]:
        this_primenum_list.append(i)

ans_list = []
while True:
    n = int(input())
    if n == 1:
        break
    i = 0
    ans = [n]
    while this_primenum_list[i] <= n:
        #print(i)
        if n % this_primenum_list[i] == 0:
            ans.append(this_primenum_list[i])
        i += 1
        if i >= len(this_primenum_list):
            break
    ans_list.append(ans)

for i in ans_list:
    print(str(i[0]) + ":", end = "")
    for j in i[1:]:
        print("", end = " ")
        print(j, end = "")
    print()