CF1443A Kids Seating

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: 1. $ gcd(a, b) = 1 $ or, 2. $ 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.

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