Antiknight Phistomefel

[PotatoHead21]

In any anti-knight sudoku, there must be at least 8 unique digits in the Phistomefel Ring. This can be proven using the above image.

If a digit is not present in the Phistomefel Ring, it must either go in the blue pedals or the green pedals. Either way, that digit always gets ruled out of the pink cells in row 5 and column 5. That means in row 5, that digit must go in box 5 and in column 5, that digit must also go in box 5, which places it in the central cell in the grid (marked in purple).

That also means you can't have more than one digit missing from the Phistomefel Ring in an anti-knight puzzle because both of those digits would have to be placed in r5c5.

[CHalb]

Hi PotatoHead21, can you please try again to attach the graphic file? Somehow it didn't work. I know error messages are sometimes not easy to spot or to interpret. Don't hesitate to ask for help, if you get unhappy with the tools in this forum.

[Raumplaner]

Hi there PotatoHead21,

I can easily follow your logic and think it's a very nice observation. Many thanks for sharing.

In any anti-knight sudoku, there must be at least 8 unique digits in the Phistomefel Ring. This can be proven using the above image.

If a digit is not present in the Phistomefel Ring, it must either go in the blue pedals or the green pedals. Either way, that digit always gets ruled out of the pink cells in row 5 and column 5. That means in row 5, that digit must go in box 5 and in column 5, that digit must also go in box 5, which places it in the central cell in the grid (marked in purple).

That also means you can't have more than one digit missing from the Phistomefel Ring in an anti-knight puzzle because both of those digits would have to be placed in r5c5.

[PotatoHead21]

Hi PotatoHead21, can you please try again to attach the graphic file? Somehow it didn't work. I know error messages are sometimes not easy to spot or to interpret. Don't hesitate to ask for help, if you get unhappy with the tools in this forum.

I don't know what you mean exactly

[PotatoHead21]

Hi there PotatoHead21,

I can easily follow your logic and think it's a very nice observation. Many thanks for sharing.

In any anti-knight sudoku, there must be at least 8 unique digits in the Phistomefel Ring. This can be proven using the above image.

If a digit is not present in the Phistomefel Ring, it must either go in the blue pedals or the green pedals. Either way, that digit always gets ruled out of the pink cells in row 5 and column 5. That means in row 5, that digit must go in box 5 and in column 5, that digit must also go in box 5, which places it in the central cell in the grid (marked in purple).

That also means you can't have more than one digit missing from the Phistomefel Ring in an anti-knight puzzle because both of those digits would have to be placed in r5c5.

Can we get Phistomefel to come look at this. I'm not sure if he already knows about this but I really want him to see this.

[Phistomefel]

That is a very cool observation, PotatoHead21! It underlines the importance of the central square in the Antiknight Sudoku. Have you though about a way to use this finding in a puzzle?

[PotatoHead21]

That is a very cool observation, PotatoHead21! It underlines the importance of the central square in the Antiknight Sudoku. Have you though about a way to use this finding in a puzzle?

As a matter of fact, I have. I used this trick in this puzzle right here: https://logic-masters.de/Raetselportal/R...?id=0007MA

[Phistomefel]

Thank you, that puzzle looks intriguing! I'll try to solve it.

[CHalb]

Hi PotatoHead21, can you please try again to attach the graphic file? Somehow it didn't work. I know error messages are sometimes not easy to spot or to interpret. Don't hesitate to ask for help, if you get unhappy with the tools in this forum.

I don't know what you mean exactly

Sorry, the problem was on my side. On my office PC the graphic was not visible and could not be opened either.