Sudoku Players' Forum (clone)

Code: Select all

 . . . 1 2 3 . . .
 . . 3 . . . 4 . .
 . 5 . . . . . 6 .
 . . . . . . 7 . .
 . . . . . 8 . . .
 . . . . . . 2 . .
 . 8 . . . . . 7 .
 . . 6 . . . 9 . .
 . . . 8 7 4 . . .   For pat, really

 . . . 1 2 3 . . .
 . . 2 . . . 4 . .
 . 5 . . . . . 6 .
 . . . . . . 3 . .
 . . . . . 1 . . .
 . . . . . . 7 . .
 . 7 . . . . . 3 .
 . . 4 . . . 5 . .
 . . . 8 6 9 . . .   extremely hard


With an extra clue one can go higher:

Code: Select all

 . . . 1 2 3 . . .
 . . 2 . . . 4 . .
 . 5 . . . . . 3 .
 . . . . . . 6 . .
 . . . . 7 4 . . .
 . . . . . . 8 . .
 . 7 . . . . . 6 .
 . . 1 . . . 3 . .
 . . . 6 4 9 . . .   even harder

extra clue, minimal, pearl:

Code: Select all

...941.....2...4...5.....3.......6......74.........8...7.....6...1...3.....659...   ED=9.4/9.4/2.6

extra clue, not minimal, pearl:

Code: Select all

...823.....2...4...5.....9.......6......74.........8...7.....6...1...3.....619...   ED=9.5/9.5/2.6

extra clue, minimal, pearl:

Code: Select all

...123.....3...4...5.....6.......7......84.........1...8.....7...9...2.....796...   ED=9.9/9.9/2.9

without extra clue, all minimal.

Code: Select all

...123.....2...4...9.....5.......3.......1.........6...7.....4...5...9.....749... ED=10.5/7.6/2.6
...283.....7...4...5.....6.......3.......9.........5...4.....1...6...8.....174... ED=10.4/10.4/2.6
...524.....3...4...5.....6.......3.......1.........2...7.....9...6...1.....879... ED=10.2/10.2/2.6
...623.....2...4...9.....5.......3.......6.........7...7.....1...5...9.....749... ED=10.1/10.1/2.6
...523.....7...4...9.....6.......6.......5.........1...8.....4...2...9.....874... ED=10.0/10.0/2.6


with extra clue, all non-minimal.

Code: Select all

...983.....8...4...1.....8.......6......25.........5...4.....6...7...3.....649... ED=10.2/10.1/2.6
...983.....8...1...2.....8.......6......51.........4...4.....6...7...3.....649... ED=10.1/10.1/2.6


with extra clue, minimal.

Code: Select all

...123.....2...4...5.....3.......6......74.........9...7.....6...1...3.....648... ED=10.0/1.2/1.2


1to9only wrote:with extra clue, minimal.

Code: Select all

...123.....2...4...5.....3.......6......74.........9...7.....6...1...3.....648... ED/10.0/1.2/1.2


Just that, that is an isomorph of the OP 'even harder'.

Mike

m_b_metcalf wrote:

Code: Select all

 . . . 1 2 3 . . .
 . . 3 . . . 4 . .
 . 5 . . . . . 6 .
 . . . . . . 7 . .
 . . . . . 8 . . .
 . . . . . . 2 . .
 . 8 . . . . . 7 .
 . . 6 . . . 9 . .
 . . . 8 7 4 . . .   For pat, really



lovely!
3.6?

Pat wrote:3.6?

ED=3.6/2.9/2.9

m_b_metcalf wrote:

Pat wrote:3.6?

ED=3.6/2.9/2.9

/2.8

(8) c7\b3
solves 8 for anti-diagonal

The /2.9 can be an indication that it is a SudokuMonster's SE rating,
where for variants, Pointing/Claiming (2.6/2.8) is disabled in favor of Generalised Intersection (2.9).
In GUI you can reenable Normal Intersections.

so, is this

.............1...2..32.4.....4......3.15.64.7......3....58.217.8...6.............

//2.6
- or //2.9 ?

There are implementation differences between (my) 1to9only's SukakuExplainer and (tarek's) SudokuMonster's SukakuExplainer.

1to9only's SukakuExplainer:

Code: Select all

.............1...2..32.4.....4......3.15.64.7......3....58.217.8...6............. ED=1.7/1.7/1.7
1st step:
1.7, Direct Pointing: Cells R4C6,R6C4: 1 of block in diagonal(/): r1c9<>1, r8c2<>1, r9c1<>1, r9c2=1


SudokuMonster's SukakuExplainer:

Code: Select all

.............1...2..32.4.....4......3.15.64.7......3....58.217.8...6............. ED=2.9/2.9/2.9
1st step:
2.9, Generalized Intersection: Cells r4c6,r6c4 on value 1 in block 5: r1c9<>1, r8c2<>1, r9c1<>1