Problem 669

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crb11
Posts: 2
Joined: Fri Nov 17, 2017 2:29 pm

Problem 669

I've come up with what I thought was a unique solution for the n=34 case, but I don't have knight 30 sitting in the 3rd chair from the king's left. My solution starts 4-30-25-9-12-... (not posting it all as I think it may give away the pattern needed to solve the puzzle). Any pointers people can give me? I'd be surprised if an error had got through this far, although there's still a typo in the text: "the king always prefers an arrangement where the knight to the his left". Thanks in advance.
crb11
Posts: 2
Joined: Fri Nov 17, 2017 2:29 pm

Re: Problem 669

Ok, I'm stupid. (I'd not realised I hadn't used all the numbers.) I now have a solution which fits the rubric.
Shogimoto
Posts: 1
Joined: Tue May 14, 2019 1:49 pm

Re: Problem 669

Ask me again about Problem 669 in the year 2040 again. I have an alogorithm, but it will run for 20 years until it prints the solution. I hope I do not run into any date problems during the wait.

Oh, I am lucky, i made an error in judging the situation: I will have the solution already in 1.92 years
mdean
Posts: 171
Joined: Tue Aug 02, 2011 2:05 am

Re: Problem 669

At this point, I'm about 1 step away from challenging the answer to this problem. I know a fair number of people have already solved this problem. I know I have everything in correctly, the program appears to operate just fine. I've done just about everything I can. Next step is to verify each step by calculator. If that checks, I'll find someone to pm to plead the best case for my answer being correct.
RobertStanforth
Posts: 1619
Joined: Mon Dec 30, 2013 11:25 pm

Re: Problem 669

mdean wrote: Mon Sep 23, 2019 8:44 am At this point, I'm about 1 step away from challenging the answer to this problem. I know a fair number of people have already solved this problem. I know I have everything in correctly, the program appears to operate just fine. I've done just about everything I can. Next step is to verify each step by calculator. If that checks, I'll find someone to pm to plead the best case for my answer being correct.
I sent you a PM.
mdean
Posts: 171
Joined: Tue Aug 02, 2011 2:05 am

Re: Problem 669

The program was working correctly. All the hand calculations were correct. One simple mistake on a limit of summation threw everything else off. My thanks to RobertStanforth for lending an ear. If I hadn't had to lay everything out to someone else, regardless of whether or not he actually reads all that, I would have been hard pressed to locate the mistake.