Sequences with no wells X41088


Statement
 

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A sequence of numbers has a well if it contains three consecutive numbers such that that the endpoints add up more than twice the one in the middle.

Formally, (x1,x2,,xn)(x_1, x_2 , \ldots , x_n) has a well if it exists at least an ii with 1i<n11 \leq i < n - 1 such that xi+xi+2>2xi+1x_i + x_{i+2} > 2\cdot x_{i+1}.

Write a program that, given an integer n1n \geq 1, writes all sequences with no well that can be obtained by reordering the sequence (1,2,,n)(1, 2, \ldots , n).

Input

The input consists of an integer n1n \geq 1.

Output

Write all sequences with no well that can be obtained by reordering the sequence (1,2,,n)(1, 2, \ldots, n). You can write the sequences in any order.

Public test cases
  • Input

    3
    
    

    Output

    (1,2,3)
    (1,3,2)
    (2,3,1)
    (3,2,1)
    
  • Input

    2
    
    

    Output

    (1,2)
    (2,1)
    
  • Input

    4
    
    

    Output

    (1,2,3,4)
    (1,3,4,2)
    (1,4,3,2)
    (2,3,4,1)
    (2,4,3,1)
    (4,3,2,1)
    
  • Input

    1
    

    Output

    (1)
    
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