Logic Masters Deutschland e.V.

I've spent many weeks getting this puzzle right. It is definitely the hardest puzzle I have set to date. You may need to use some geometry techniques such as the "Phistomefel ring" and I've given some hints at the bottom of the page on divisibility rules that you will need to know. Good luck!



Rules:

• Normal sudoku rules apply.
• In cages, digits must sum to the small clue in the top left corner of the cage. Digits can repeat in the 99 cage.
• Digits along arrows sum to the value in the attached circle.
• The “99” on the outside of the grid represents the 9-digit number in that row or column must be divisible by 99.
• The three (straight) green lines (two 7-digit and one 4-digit number) are also divisible by 99.
• Digits may not repeat on each main diagonal.


f-puzzles link
CTC app link - If using the ctc app make sure to select Conflict Checker "On (simplified)", so that conflicts in the 99 cage do not show up.

Hint: Test for divisibility of 9

If the sum of all digits is divisible by 9, then the original number is divisible by 9.

Hint: Test for divisibility of 11

If the difference between the sums of alternating digits is divisible by 11 (or zero), then the original number is divisible by 11.

Examples:

• 9583761 is divisible by 11, as (9+8+7+1)-(5+3+6) = 25-14 = 11
• 53174 is divisible by 11, as (5+1+4)-(3+7) = 10-10 = 0


Divisibility Rules series:

Maths Factor - A nicely flowing puzzle with divisibility by 2 to 9 logic.
This one goes up to 11! - Has similar divisibility by 11 logic to this puzzle, but much easier.