Symmetric Odd-Even Sudoku possible?

Everything about Sudoku that doesn't fit in one of the other sections

Symmetric Odd-Even Sudoku possible?

I want to make a symmetric odd/even sudoku, where not only the clues but also the colored grid is symmetric. (i. e. if R1C2 is an odd number then also R9C8 should be odd, and if R1C3 is even then also R9C7 should be. R5C5 must be odd of course. Or saying it in other way I look for a way to color a sudoku grid so that in every row, column and box are 4 green and 5 yellow cells.

Any other symmetry or a jigsaw variant would also be nice. But I can't find a possible grid. Any idea?
Pyrrhon

Posts: 240
Joined: 26 April 2006

Keith
keith
2017 Supporter

Posts: 216
Joined: 03 April 2006

No deadly pattern in this puzzle.

Here is an example from the Superior Thread, by Red Ed. The colors are mine.

This puzzle has a little extra, but it's a start, you can do a little scrambling and minimization.

Ruud.
Ruud

Posts: 664
Joined: 28 October 2005

You can do better than just symmetric odd/even: you can have opposite cells summing to 10.

Ah! I see Ruud's pipped me to it!

You can do odd/even symmetry for quarter turns, too:
Code: Select all
`# 2 . 5 . . # . #. # 1 3 . # . # 4# . 9 # # # 3 7 .. # # . 2 . # 2 5. . # 6 . 4 # . .5 9 # . 8 . # # .. 3 7 # # # 1 . #6 # . # . 7 9 # .# . # . . 5 . 8 #Key: . = odd     # = even`
Red Ed

Posts: 633
Joined: 06 June 2005

Thank,

nice extra idea.

Pyrrhon
Pyrrhon

Posts: 240
Joined: 26 April 2006