Problem 331

sivakd · Post by **sivakd** » Wed Apr 06, 2011 7:58 am

3 days since the problem came out and now I seem to finally have a method to compute for smaller N though not sure as I can only calculate for some values of N and not the other. Is it ok to ask if T(20) is of the form XYX?

sivakd · Post by **sivakd** » Wed Apr 06, 2011 9:41 am

Never mind, I can confirm T(1000) as given in the problem.

pinguin · Post by **pinguin** » Fri Apr 08, 2011 5:26 am

Try it

http://www.eelvex.net/games/pe-331-game/

sivakd · Post by **sivakd** » Fri Apr 08, 2011 5:55 am

LOL. That's a good one. Have you solved the puzzle yet? If so, you can even have a solver.

Also, cool that you used Processing.js . I used this nice library recently for one of my personal projects.

pinguin wrote:Try it

http://www.eelvex.net/games/pe-331-game/

phsr · Post by **phsr** » Fri May 06, 2011 9:08 pm

I have an efficient algorithm that appears to work for all values that I can verify independently, but my solution is wrong and I am struggling to figure out why.

Would someone be willing to tell me if the sum of the 4 last terms (i = 28 to 31) ends with 639?

ffff0 · Post by **ffff0** » Thu Mar 15, 2012 5:22 am

I'm really struggling with this one. I have a feeling that this sort of flipping is some classic game/puzzle, but I've failed to find any references. Can anyone tell me, what it is? I'm in desperate need of a starting place.

jaap · Post by **jaap** » Thu Mar 15, 2012 6:45 am

ffff0 wrote:I'm really struggling with this one. I have a feeling that this sort of flipping is some classic game/puzzle, but I've failed to find any references. Can anyone tell me, what it is? I'm in desperate need of a starting place.

It is Lights Out with a different move shape or Alien Tiles with only 2 colours.

ffff0 · Post by **ffff0** » Thu Mar 15, 2012 6:51 am

Thanks!

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