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OVER_EIGHT

                                           February  4, 2015
                                           December 16, 2014
                                                      
While I was trying to reproduce a feat of             
brilliance from many a year ago, I actually           
got the name of the puzzle wrong, and hence            EIGHT_QUEENS
felt completely confused about what was going         
on:  instead of the 8 queens problem, I thought       
it was the 9 queens problem.  Now, there *is*          IN_THE_IRON_MASK
an 9 queens problem that I must've heard about           MEMORY
at some point, and that was probably the source       
of the confusion, but it's completely different,      
it allows addition of one or more pawns.              
                                                      
A little bit of thought should've                     
shown that what I was trying to                       
remember couldn't possibly have           This did not stop me from
involved 9 queens-- it's a complete       trying to reason out a way
impossibility.                            this impossibility might be
                                          accomplished: "hm, could it
My false memory had me completely         be there's room in the
tangled up, I didn't tumble to the        middle of this square for
obvious until after a long process        one more queen?"
of going back and forth through                     
the logic.                                            
                                                      
   I carefully worked this out, to                    
   convince myself I'd made no mistake:               
                                                      
     Every piece must have a row and column,              
     Every queen attacks along one row and one column.
     Doubling a queen in either a row or a column     
     would have them attacking each other.            
     There are only 8 rows, and 8 columns.                
                                                          
   A fine example of plodding, laborious                  
   thinking, the precise opposite of the                  
   intuitive leap I wanted to talk about.                 
                                           EIGHT_QUEENS
                                             
                                             
                                             


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