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       #Post#: 35--------------------------------------------------
       a method to create symmetric closed magic knight tours on 4m*4n 
       rectangles
       By: gsgs Date: March 13, 2024, 11:41 am
       ---------------------------------------------------------
       here is a file with 15 of these 4ssy-tours , as i called them ,
       together with their two generating king-tours :
  HTML http://magictour.free.fr/4ssy.l2
       they all start on (m/2-2,n) and end on (m/2-1,n-2).
       They have 8 parts of equal length and form.
       Parts 1 and 2 are created by generating 2m*2n king-tours
       part 3 is Sy(part 1) reversed
       part 4 is Sy(part 2) reversed
       part 4+i is Sxy(part i) for i=1,2,3,4
       Sy=horizontal reflection
       Sxy=180' - rotation
       All but 8 edges have their 2 reflections included in the tour.
       -------------------------
       I haven't yet figured out the clear rule
       which creates these 4ssy-tours for all rectangles 4m*4n
       --------edit 2024-03-15----------------
       I think I found a pattern now , how to create a
       4m*4n (m>2,n>2) 4-semi0symmetric magic knight tours,
       generated by 2m*n double-king tours
       2 methods, depending on whether m is odd or even
       here is a simple Basic program which prints 4m*4n  4ssy tours :
       http:\\magictour.free.fr/AUT9.BAS
       see :
       [code]
       
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       [/code]
       C-program to generate these :
  HTML http://magictour.free.fr/4ssymkt.c
       ------update 2024-03-26-------------
       above program now creates 4m*4n symmetric magic knight tours
       for m,n>=2
       with generating king-tours of length 4mn
       ----------update 2024-03-28---------------
       here a file with the tours upto size 32*32 :
  HTML http://magictour.free.fr/sy32.txt
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