Black Magic Square
(Published on 21. September 2025, 22:57 by billybeth)
On green lines each digit is at least five different from its predecessor.
Complementary Rotation. If the whole board is rotated by 180 degrees and the new digits added to their previous each square contains ten.
One of the nine boxes is a Magic Square, one is a Black Magic Square and one is a Blacker Magic Square.
In a magic square each line of three cells vertically, horizontally and diagonally add to the same total
The Black Magic Square is similar but here the two outside digits of the groups of three are added and the central one is subtracted to always give same total.
The Blacker Magic Square is also similar but here the two outside digits are subtracted from central one of the three to give the same total in all cases.
The black dot separates two cells in the ratio 1:2. Not all black dots are given.
Solve online:Sudokupad
Solution code: top row
Comments
on 25. September 2025, 23:49 by Da Letter El
can confirm that the rules as written now do have a unique solution
sort of a shame that the definition of black magic squares and blacker magic squares changed because after the change the most interesting part of the puzzle sort of went away
on 25. September 2025, 20:10 by billybeth
Hello proNoob. Many thanks for looking into our puzzle, you are the only one to tackle it as far as we know! First we have to make an apology - the ruleset we put out was an earlier version that did not include the disambiguation of asking that the digits of the black magic squares had to be in a certain order. The third of your possible solves does indeed satisfy the previous instructions which we have now updated. maybe now you know these new rules you can update your solution which is very close. by the way the four other of your solves may have a problem with the 3 and 7 in top line rotating and contradicting??? anyway congratulations on being the first to solve a version of the puzzle and apologies again. billybeth
on 25. September 2025, 19:43 by billybeth
revised instructions
on 25. September 2025, 15:57 by proNoob
Yeah, I found that 3-7 pair problem this morning. Thank you for responding.
on 25. September 2025, 15:51 by proNoob
um... I found multiple solutions (five, more precisely) but no one fits the solution code. Is there some problem with the code or am I going wrong?
on 23. September 2025, 22:37 by billybeth
updated instructions
on 23. September 2025, 22:36 by billybeth
clarified rules
on 23. September 2025, 22:33 by billybeth
to Da Letter EI. no, at least one box is a MS, at least one is a BMS and at least one one is a BerMS. thanks for the clarification.
on 23. September 2025, 20:49 by Da Letter El
is it important to assume that ONLY one box is a magic square, ONLY one box is a black magic square, and ONLY one box is a blacker magic square?
on 23. September 2025, 08:51 by billybeth
changed difficulty as no one has solved
on 22. September 2025, 08:39 by billybeth
thanks for advice villse
on 22. September 2025, 08:38 by billybeth
added link
on 21. September 2025, 23:10 by Villse
<p>Solve online:<a href="https://sudokupad.app/7zwmfl5yg0">Sudokupad</a>
If you want to add a link instead :)
