Comments on: Kenken

By: Jacy

Jacy — Sat, 07 Nov 2009 01:34:22 +0000

hi, I didn’t know where to contact you but your layout looked rearranged on firefox and internet explorer. Anyways, i just suscribd to your rss.

By: John Gilbrough

John Gilbrough — Tue, 01 Sep 2009 12:44:08 +0000

Brian -

First, thank you for all your excellent work on describing KenKen puzzles. This is one of the first places I came to when I got “hooked”.

As much as I enjoyed playing KenKen, I soon grew tired of the awkward players available, so I developed my own. You can view this at the URL above.

The reason I am writing you is that I’ve used both of the puzzles that you have on this page within my list of puzzles, and I want to get your permission for that.

So please check out what I’ve done, and let me know what you think.

Thank you,

John Gilbrough

Professor Homunculus sez:

Thanks for your comment at the Chronicles. I checked out your player, and it is very cool.

The puzzles on my site (all of them) were given to me to use by the people at Nextoy, LLC (they own the KenKen trademark), so I can’t give you my permission to use them.

If you contact them, you can ask them. They seem very reasonable, and are really trying hard to get the “message” of math with KenKen out there.

By: Steven

Steven — Tue, 25 Aug 2009 02:40:11 +0000

Wow, just started and this really helped. Thanx soo much, now i understand.

By: jeremy

jeremy — Sat, 25 Jul 2009 19:19:42 +0000

One more thing. Another great exercise is to memorize the grid first in your head and do everything in your head then, without ever looking back at the screen, everything memorized. Can’t do it with this one though, but I’ve doen up to 7×7 like that. Takes a reaaally long time, but again, real good for your brain in lots of different ways. Writing everything down is kind of wasting the whole point of the puzzle in my opinion since you’re ultimately looking for brain stimulation.

Professor Homunculus sez:

Jeremy,

Thanks for your thoughts. I also do most of these without writing. I am have been doing mnemonics for quite a few years, though. I feel, as you do, that doing it like that is a great brain-building tool.

By: jeremy

jeremy — Sat, 25 Jul 2009 19:17:23 +0000

This is great, I had a lot of fun, thank you. But you shouldn’t write anything down. I do everything in my head. It takes more time but is much better for your brain.

By: Jan

Jan — Tue, 07 Jul 2009 21:04:45 +0000

Me again. Still working through your videos. I’m checking to see how much of my Sudoku logic applies to KenKen as well. Here’s the question. I just watched Step 13, where you filled out the cells for possible combos to make 24, and got the possible entries of 3,4,6,8. When I look further across the row, I see another cell that only contained some of those numbers in it. In other words, 3,4,6,8 HAVE to be in one of those four cells. Doesn’t that mean one can eliminate them at this time as possibilities for any other cells in that row?
Or would I be getting myself in trouble by doing that?
(By the way, I do realize that there are multiple ways of solving any kenken, so this isn’t meant as a criticism.) :)

Professor Homunculus sez:

Jan,

No worries – your input is very constructive. The real reason I started these vids is to get input exactly like what you are giving me, so I can learn as well.

Yes, the rules for sudoku hold as well for Kenken, except for the “quadrants” (which in the case of a 9×9 cell would be the “ninths” or whatever a square of 9 cells would be called).

You’re way ahead of me, though. Be patient. You are right, of course, and we get to it in lesson 15.

Can you do me a favor? Keep track of your questions, and when you get to the end of the series, let me know if any of them never get addressed. Some may not, because sometimes I’ll attack a problem from a different angle, but if you see an angle that I missed, let me know in a comment, so other people can see that there is more than one way to skin a KenKen.

You may find that some of your questions are answered in a video further down the line, though, so wait till you’ve been through the bunch of them, OK?

Your input is very, very welcome.

All the best,

Brian

By: Jan

Jan — Tue, 07 Jul 2009 19:41:16 +0000

I’m fairly new to KenKen, so please forgive if I miss something obvious. I just viewed Step 5 of your 9×9. Why did you not list 1 as a possible factor for you 630 cage? Also, when you completed your 315 cage, you said that you could not erase any factors at this time. I thought you could already erase the 5 and the 7 as possibilities for the 7th row of the 315 cage, because they are already definites elsewhere in that row. That would mean that cell must contain the 9.

By the way, thanks for the videos. I am enjoying your logic.

Professor Homunculus sez:
Jan,
Those are pretty good questions. The reason why you can’t have a 1 in the 630 cage is because you have 4 cells, and you have 4 prime factors. Each of those prime factors must be be used in at least one of the cages. The 2 must be used – be it in the form of a 2, or a two as a factor of another number, like 6. Same for the 3, it must be used as a 3, 6, or a 9, but it must be used.

Just try to make 630 by multiplying four digits and see if you can finagel a 1 amongst them. If you can, let me know how you did it!

As far as your second point – the one about getting rid of the 7 and 5 in the bottom row of the 315 cage – you are 100% right.

The problem with making these videos is that there are many possibilities at any time, and different people see different ones at different times. There is no “official order” as to how to solve a kenken puzzle. (Well, maybe there is for a computer program, but I imagine that there is not even an optimal universal algorithm for computers, either ).

Considering that I try to keep the vids to under 10 mins, I basically only show what I focus on during that time.

It is true though, that I should have seen that immediately. You’ll find that no matter how good you get, there is always chance for oversight. That’s why I occasionally do a random ecology check of a row, column, or the whole puzzle.

When you get to video # 7, you’ll see that I mention that I’d overlooked what you caught much earlier. Good thinking! And thanks for the comment.

Hotcha!

Brian (a.k.a. Professor Homunculus)

By: John

John — Tue, 30 Jun 2009 21:08:19 +0000

Just completed this video series- Excellent. My game has certainly improved, thanks. Looking forward to your membership blog and future videos.

By: Marianne

Marianne — Tue, 26 May 2009 04:02:07 +0000

This is pretty tough. I’ll try too solve a kenken puzzle one of these days.

Thanks for dropppin by.

By: Sherry Barnhart

Sherry Barnhart — Thu, 30 Apr 2009 16:41:44 +0000

Great video on the simple KenKen! I’ve been frustrated by the 6×6 puzzles my local paper started this week, but this has given me new hope. I think I’ll work on the 4×4’s until I build up some confidence. Thanks!