Has anyone noticed this idiosyncrasy?

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Has anyone noticed this idiosyncrasy?

Postby abrooks051 » Tue May 12, 2015 8:57 pm

Hello,I have played for several years, and I love it. However, I found a slight "glitch". After playing several thousand games it occurred to me that I never solved a game where any one line, vertical or horizontal, was solved with the numbers going in series. (eg. 1-9 or 9-1). Am I alone here??
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Re: Has anyone noticed this idiosyncrasy?

Postby Leren » Wed May 13, 2015 2:09 am

Try solving this puzzle. The first row in the solution should be 123456789

Code: Select all
1........
......4.6
4...18325
8...3.24.
........7
....2...8
23...58..
7.49.....
..9.....3

Leren

<edit>

Just thinking about this a bit further, the number of permutations of digits in a row or column is 9 ! (9 Factorial = 9*8*7*6*5*4*3*2*1) = 362,880

You have 9*2*2 = 36 ways of being satisfied, so the probability that a random puzzle that meets your requirements is 362,880/36 = 10,080

Maybe you just haven't 'solved enough puzzles yet.

Leren
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Re: Has anyone noticed this idiosyncrasy?

Postby abrooks051 » Wed May 13, 2015 11:05 am

Leren,
Thank you for the help. Math was never one of my best subjects. I thought I had done quite a few games but it seems I have quite a few to go.
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Re: Has anyone noticed this idiosyncrasy?

Postby Leren » Wed May 13, 2015 12:00 pm

If you solve 1 puzzle a day you should find a suitable puzzle on average about once every 27.6 years !

However you can always swap the clues around in any puzzle to get what you want. Here's how:

In the example puzzle I gave you the bottom row solves to 689241573. Now suppose you wanted to see a solved puzzle with the bottom row solved to 987654321

689241573 is what you have in the bottom row.
987654321 is what you want in the bottom row.

All you have to do to get from what you have to what you want is to swap each clue from the top line to the bottom line. So if the puzzle has a clue 6 change that clue to 9 leave 8 as 8, change 9 to 7, 2 to 6 etc all the way along the 2 lines.

The puzzle will solve exactly the same way as before but you will find that the bottom row is 987654321 !

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Re: Has anyone noticed this idiosyncrasy?

Postby m_b_metcalf » Wed May 13, 2015 12:12 pm

Here' a very hard one with six empty rows and columns to keep you guessing:
Code: Select all
 . . 4 8 . 3 1 . .
 . 8 9 2 . 1 4 3 .
 . . . . . . . . .
 . 4 5 . . . 9 2 .
 . . . . . . . . .
 . 1 8 . . . 3 6 .
 . . . . . . . . .
 . 3 2 1 . 5 6 9 .
 . . 1 3 . 2 8 . .


Regards,

Mike Metcalf
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Re: Has anyone noticed this idiosyncrasy?

Postby abrooks051 » Wed May 13, 2015 5:00 pm

Leren,
I'm 63 so I guess I better do more than one puzzle a day :lol:
Alan
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Re: Has anyone noticed this idiosyncrasy?

Postby Yogi » Thu May 19, 2016 8:55 pm

And here's another: 1...5.......1...6...4...2...7...3...5...2...8...6...7...6...3...3...7.......4...1
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Re: Has anyone noticed this idiosyncrasy?

Postby Leren » Thu May 19, 2016 10:01 pm

Hi Yogi, just tried your puzzle and it solved (apart from basic mark-offs and singles), with just one naked triple in Column 5. You really like those naked triples ! :D

Leren
Last edited by Leren on Fri May 20, 2016 6:30 am, edited 1 time in total.
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Re: Has anyone noticed this idiosyncrasy?

Postby Leren » Thu May 19, 2016 10:21 pm

I just tried solving Mike's puzzle by normal methods. It wasn't too hard, but I noticed that there were a lot of single digit moves on 7. That suggested template analysis.

Not too surprisingly the puzzle solved with a single non-basic move : single digit template analysis on 7 :

Code: Select all
*--------------------------------------------------------------*
| 2567 *7-256 4      | 8     5679  3      | 1     57    29     |
| 57    8     9      | 2    *7-5   1      | 4     3     6      |
| 1     2567  3      | 4679  45679 4679   |*7-5   8     29     |
|--------------------+--------------------+--------------------|
| 367   4     5      | 67    13    678    | 9     2     18     |
| 23679 2679 *7-6    | 45679 13    46789  | 57    457   18     |
| 79    1     8      | 4579  2     479    | 3     6     7      |
|--------------------+--------------------+--------------------|
| 45678 5679  67     | 4679  46789 4679   | 2     1    *3-45   |
|*7-48  3     2      | 1     478   5      | 6     9     47     |
| 4679  679   1      | 3     4679  2      | 8    *7-45  457    |
*--------------------------------------------------------------*

Single digit template analysis on 7 => r1c2, r2c5, r3c7, r5c3, r7c9, r8c1 and r9c8 = 7; stte

Here's the solution:

Code: Select all
*--------------------------*
| 6 7 4  | 8 9 3  | 1 5 2  |
| 5 8 9  | 2 7 1  | 4 3 6  |
| 1 2 3  | 4 5 6  | 7 8 9  |
|--------+--------+--------|
| 3 4 5  | 6 1 7  | 9 2 8  |
| 2 6 7  | 9 3 8  | 5 4 1  |
| 9 1 8  | 5 2 4  | 3 6 7  |
|--------+--------+--------|
| 8 5 6  | 7 4 9  | 2 1 3  |
| 7 3 2  | 1 8 5  | 6 9 4  |
| 4 9 1  | 3 6 2  | 8 7 5  |
*--------------------------*

Row 4 will keep abrooks051 happy and the template solution will keep people who like computer solutions happy.

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Re: Has anyone noticed this idiosyncrasy?

Postby Yogi » Fri May 20, 2016 2:22 am

Actually, the puzzle I posted was one from a list of 851 puzzles of that pattern and it seems that they are all rated as MILD, whatever that means. I'm getting a bit bored with them myself. I just happened to notice that the solution included a numerical 1-9.
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Postby Pat » Fri May 20, 2016 7:33 am

Yogi wrote:Actually, the puzzle I posted was one from a list of 851 puzzles of that pattern and it seems that they are all rated as MILD, whatever that means. I'm getting a bit bored with them myself. I just happened to notice that the solution included a numerical 1-9.

{ off-topic }

"mild" ? all ??
Code: Select all
 1 . . | . 5 . | . . .
 . . . | 2 . . | . 3 .
 . . 4 | . . . | 6 . .
-------+-------+------
 . 9 . | . . 3 | . . .
 6 . . | . 7 . | . . 5
 . . . | 1 . . | . 7 .
-------+-------+------
 . . 1 | . . . | 2 . .
 . 3 . | . . 9 | . . .
 . . . | . 6 . | . . 1
    1...5.......2...3...4...6...9...3...6...7...5...1...7...1...2...3...9.......6...1
    [ play ]
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Postby Yogi » Fri May 20, 2016 10:45 pm

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