# It's all in the title...

Take as input a positive integer `n>=12` and... do what the title says.

Yes, this is on OEIS [A187924][1].

**Some test cases**  

    12 -> 912  
    13 -> 11713  
    14 -> 6314  
    15 -> 915  
    16 -> 3616  
    17 -> 15317  
    18 -> 918  
    19 -> 17119 
    20 -> 9920  
    40 -> 1999840   
    100-> 99999999999100

This is [Tag:code-golf]. Shortest code in bytes wins!

  [1]: https://oeis.org/A187924