Kids Seating (Codeforces 1443A)
Tags: Math, constructive algorithms

Today the kindergarten has a new group of $$$n$$$ kids who need to be seated at the dinner table. The chairs at the table are numbered from $$$1$$$ to $$$4n$$$. Two kids can't sit on the same chair. It is known that two kids who sit on chairs with numbers $$$a$$$ and $$$b$$$ ($$$a \neq b$$$) will indulge if:   $$$gcd(a, b) = 1$$$ or,  $$$a$$$ divides $$$b$$$ or $$$b$$$ divides $$$a$$$. $$$gcd(a, b)$$$ — the maximum number $$$x$$$ such that $$$a$$$ is divisible by $$$x$$$ and $$$b$$$ is divisible by $$$x$$$.For example, if $$$n=3$$$ and the kids sit on chairs with numbers $$$2$$$, $$$3$$$, $$$4$$$, then they will indulge since $$$4$$$ is divided by $$$2$$$ and $$$gcd(2, 3) = 1$$$. If kids sit on chairs with numbers $$$4$$$, $$$6$$$, $$$10$$$, then they will not indulge.The teacher really doesn't want the mess at the table, so she wants to seat the kids so there are no $$$2$$$ of the kid that can indulge. More formally, she wants no pair of chairs $$$a$$$ and $$$b$$$ that the kids occupy to fulfill the condition above.Since the teacher is very busy with the entertainment of the kids, she asked you to solve this problem.

Input: The first line contains one integer $$$t$$$ ($$$1 \leq t \leq 100$$$) — the number of test cases. Then $$$t$$$ test cases follow.Each test case consists of one line containing an integer $$$n$$$ ($$$1 \leq n \leq 100$$$) — the number of kids.

Output: Output $$$t$$$ lines, which contain $$$n$$$ distinct integers from $$$1$$$ to $$$4n$$$ — the numbers of chairs that the kids should occupy in the corresponding test case. If there are multiple answers, print any of them. You can print $$$n$$$ numbers in any order.


Sample Inputs:
3
2
3
4

Sample Outputs:
6 4
4 6 10
14 10 12 8

Solution (Python):
for _ in range(int(input())):
    n = int(input())
    print(*range(n * 2, n * 4, 2))

Solution (Python):
def solve():
    n = int(input())
    for i in range(1, n + 1):
        print(4 * n - 2 * i, end=' ')
    print()
if __name__ == '__main__':
    for test in range(int(input())):
        solve()

Solution (Python):
import itertools
for _ in range(int(input())):
    n = int(input().strip())
    print(' '.join(map(str, list(range(2 * n, 1 + 4 * n, 2))[:n])))