(HP-67/97) a little fun with the fifteen puzzle

[Don Shepherd]

(12-06-2016 01:43 AM)SlideRule Wrote:  Maybe post the 17b solver equation if anyone shows an interest? {hint}

SlideRule

Sure, SlideRule, here it is:

Code:


FIFTEEN:SIGMA(I:1:16:1:IF(ITEM(C:I)=0:IDIV(I+3:4):0))+SIGMA(I:1:15:1:SIGMA(J:I+1​:16:1:IF(ITEM(C:J)<>0 AND ITEM(C:J)<ITEM(C:I):1:0)))-INV

solve for INV, sum list C contains the 16 values, 0=empty cell