The New Sudoku Players' Forum

[denis_berthier]

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SudoRules doesn't combine unlikely patterns into "unlikely to the square" patterns. It is based on precise rules giving a priority to smaller patterns and shorter chains, which are statistically much more efficient.

This puzzle was proposed as an extremely rare puzzle in B19. Because it is derived from a puzzle with a tridagon, it still has patterns close to the tridagon and it can be solved more easily by using them. Which patterns are used precisely to this purpose is quite irrelevant.
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[eleven]

Yes, just as the Sudo Rules are quite irrelevant for manual solvers.

[denis_berthier]

.
and of course, you consider yourself as the ultimate judge of what manual solvers are interested in...
.

[totuan]

Below puzzle from http://forum.enjoysudoku.com/the-layered-structure-of-t-e-depth-d-t45647.html#p352761 can downgrade faster by using UR/DPs.
Don't think this is smart, just feel: why don't use it…
B21:

Code: Select all

12.........6....2378..3.......56..9...59.1..6....23.15.9..1....5..69..32...3....1  #3306

Hidden Text: Show

Code: Select all

 *--------------------------------------------------------------------------------*
 | 1       2       3       | 478     478+5  *56(4789)| *56+478    45678   4789    |
 | 49      5       6       | 1478    478     4789    |  1478      2       3       |
 | 7       8       49      | 12      3      *56(2)   | #56+1    *#56      49      |
 |-------------------------+-------------------------+----------------------------|
 | 248     1347    12478   | 5       6       478     |  23        9       478     |
 | 248     347     5       | 9       478     1       |  23        478     6       |
 | 4689    467     4789    | 478     2       3       |  478       1       5       |
 |-------------------------+-------------------------+----------------------------|
 | 3       9       2478    | 2478    1       2478+5  |*#56(478) *#56(478) 478     |
 | 5       147     1478    | 6       9       478     |  478       3       2       |
 | 2468    467     2478    | 3       478-5   24578   |  9         4578    1       |
 *--------------------------------------------------------------------------------*

UR(56)r37c78 #-marked cells => (5)r7c6=(1)r3c7
MUG(56) *-marked cells => (5)r1c5=(5)r7c6=(478)r1c7

01: (5)r7c6==(1)r3c7-(1=478)r268c7-(478)r1c7==(5)r1c5,r7c6 => r9c5<>5, r1c5=5

Code: Select all

 *-----------------------------------------------------------------------*
 | 1      2      3      | 478    5      46789  | 4678    4678     4789   |
 | 49     5      6      | 1478   478    4789   | 1478    2        3      |
 | 7      8      49     | 12     3      26     |*56+1   *56       49     |
 |----------------------+----------------------+-------------------------|
 | 248    1347   12478  | 5      6     #478    | 23      9       #478    |
 | 248    347    5      | 9     #478    1      | 23     #478      6      |
 | 4689   467    4789   |#478    2      3      |#478     1        5      |
 |----------------------+----------------------+-------------------------|
 | 3      9      2478   |#478+2  1      24578  |*56(478)*56(478) #478    |
 | 5      147    1478   | 6      9     #478    |#478     3        2      |
 | 2468   467    2478   | 3     #478    24578  | 9      #478+5    1      |
 *-----------------------------------------------------------------------*

Tridagon(478) #-marked cells => (5)r9c8=(2)r7c4
UR(56)r37c78 => (1)r3c7=(5)r9c8
02: (5)r9c8==(2)r7c4-(2=1)r3c3-(1)r3c7==(5)r9c8 => r9c8=5 then ER-6.6 and easy to finish

Thanks for the puzzle!
totuan

[eleven]

.and of course, you consider yourself as the ultimate judge of what manual solvers are interested in....

Oh no, just my personal opinion.

Below puzzle from http://forum.enjoysudoku.com/the-layered-structure-of-t-e-depth-d-t45647.html#p352761 can downgrade faster by using UR/DPs.
Don't think this is smart, just feel: why don't use it…

Nice!