Logic Masters India announces November Sudoku Test — Renban Groups

Author : Zafer Hüseyin Ergan

Date : 13^th and 14^th November

Sudoku Types : 10 types, 1 6X6 and 1 9X9 from each type. Each Sudoku has Renban Group constraints

Length : 100 minutes

IB and Submission Link : http://logicmastersindia.com/lmitests?test=M201011S

and what exactly are the Renban Group constraints? :)

Please spend a moment checking the IB OR the submission page OR both :-)

Here it is -
Each Renban Group is a set of grey painted cells connected to each other, either orthogonally or diagonally. Each Renban Group must hold distinct consecutive digits, in any order. Renban groups may cross across 3X3 boxes / 2X3 boxes / irregular regions.

Oops.. my bad... Didnt notice that the IB was already up :)

In the shifted Sudoku, can it be assumed that the actual sudoku is a torroidal sudoku with the renban group constraint?? In the Ib the author mentions that the position of the 1-6 digits is incidental... not sure what is intended?

Rishi

Hi Rishi,

Yes it is actually a toroidal sudoku with the renban group constraint.

I marked the standard 2x3 blocks with red rectangles in the solution of the example. If you check
this you can see that digits 1 to 6 are placed exactly once into those red rectangles. But it is not
necessary which means that there may be duplicating digits in those red rectangles. Extra note just
try to explain this is an incidental situation. I have designed also a 9x9 shifted sudoku with renban
groups for the puzzle portal of German site http://www.logic-masters.de/. Here is the direct link for
that one:

http://www.logic-masters.de/Raetselportal/Raetsel/zeigen.php?id=000...

If you try to solve this one with given rules you'll see that there will be some duplicating digits inside
the standard 3x3 blocks.

I hope the explanation is helpful.

Zafer





Attachments
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shiftedsudwithrbg.JPG (22KB - 2 downloads)

Chinese version is available on http://www.sudokufans.org.cn/forums/index.php?showtopic=125
if you want to play examples online, click the image of puzzle on the left. ( please use IE7/8 or Chrome)

Thanks Zafer...

The explanation is indeed helpful :) Looking forward to the test..

Rishi

solved the example on LM Germany and it was really a great puzzle.. :)

Rishi

for Chinese translation. It is also very good that the examples may be played online I tried also playing in Firefox and I can say there was no problem also in Firefox

Regards,

Zafer

Hi Rishi,

for your kind words I'm glad you liked it. I wish you will also enjoy the actual
puzzle during the test.

Zafer

In the note for Shifted Sudoku, it says 'The numbers 1~6 must not occur in standard 2x3 boxes'. 'Must not occur' or 'May not occur'?

Hi Rohan,

It is actually stated that
"In the example numbers 1~6 is occured once inside standard 2x3 blocks. But it is not a MUST. Therefore there may be some duplicating digits inside these 2x3 standard blocks for 6x6 shifted sudoku (and 3x3 standard blocks for 9x9 shifted sudoku)".

In order to clearify this note I'll try to prepare a 6x6 shifted sudoku with renban groups in which there exist duplicating digits inside 2x3 standard blocks and try to share it here soon.

Regards,

Zafer

Here comes my new 6x6 shifted sudoku design.

Regards,

Zafer





Attachments
----------------
shiftedsudwithrbgex2.JPG (18KB - 8 downloads)

Rohan, it is "May not occur".
It is basically a Toroidal Sudoku with special shapes of 2X3 or 3X3 blocks. [ So it should be much easier than a toroidal sudoku ]

Zafer, thanks for uploading another example.

Ok. Got it. Thanx Zafer and Deb.

Looking forward to this test :-)

Hi to all. Here comes the answer of my second 6x6 shifted sudoku example. You can see the duplicating digit or digits inside the standard 2x3 blocks.



Thanks Deb for your help on spoiler usage.

Regards,

Zafer

Edited by zhergan 2010-11-04 1:15 PM

I'm looking forward to this one and have managed to complete all the 6 x 6s in the instruction booklet apart from one - the Symmetric Unequal Sudoku. I expect I'm missing something really obvious but I can't work out which cells are 180 degrees symmetric to each other.
Can anyone try and explain it to me please? Thanks.

Hi,

In the symmetric unequal sudoku cells that are 180° symmetric to each other
cannot have same digits.

Keeping in mind that R corresponds to row and C corresponds to column; If
we talk about 6x6 R[n]C[k] can never have the same digit as R[7-n]C[7-k]
all n, k from 1 to 6 and if we consider 9x9 this time R[n]C[k] can never
have the same digit as R[10-n]C[10-k] for all n, k from 1 to 9 (of course
not both 5 same time).

Try to apply this rule once. You'll see it works. Hope it is more clear now.

Regards,

Zafer

And who are interested about symmetric unequal sudoku may try to solve my 9x9 example on LM Germany site with the following address:

http://www.logic-masters.de/Raetselportal/Raetsel/zeigen.php?id=000...

It is not a hard one also. You may try it as an exercise.

Zafer

Yes - I've got it now! Thanks for taking the time to reply - I've never come across this sudoku variant before. It's always great to come across a new puzzle type so I will go and try out the 9 x 9 now!

Regards. Christine

Some more Symmetric Unequal Sudokus from our older tests (without renban constraints)

From Classic Look Alikes

Click here to solve online

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From Classic Look Alikes

Click here to solve online

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from Mock 12

Click here to solve online

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from Mock 12

Click here to solve online

Hi,
I cannot see any link to the IB for the test. Is there something that I am missing?
Munira.

If you are using a small screen computer, please scroll towards your right.
We are having this problem for a while now. High time we get it fixed :-)