The Math Advent Calendar is celebrating its 20th anniversary this year!
To celebrate and build excitement for this year’s Advent calendar, we’ve come up with a few small puzzles. For questions or feedback, we are available in the forum.
Have fun solving them!
20 Years Math Advent Calendar – Nonogram
Rules:
- Color the gray cells of the grid black and white by clicking on them.
- Clues left to the grid give the number of black cells in a contiguous sequence in that row in order.
- Clues above to the grid give the number of black cells in a contiguous sequence in that column in order.
- Two contiguous sequences of black cells are seperated by at least one white cell.
20 Year Anniversary (Masyu)
Link: https://tinyurl.com/2cbmjf3q (Puzzle in Penpa+)
Rules:
- Draw a single closed loop in the grid, that does not visit a cell more than once. The loop must not branch.
- The loop only moves orthogonally (between cells sharing an edge) and never diagonally.
- The loop must visit all cells with black or white circles in it but not necessarily all other cells.
- In a cell with a black circle the loop must make a 90° turn and must travel straight trough the previous and next cell.
- In a cell with a white cell the loop must travel straight and must turn 90° on the previous and/or next cell.
20 Year Anniversary (Sudoku)
Link: https://tinyurl.com/22qbougv (Puzzle in Penpa+)
Rules:
- Normal 6×6 sudoku rules apply, i.e. place the digits 1-6 once in every row, column and box.
- Cages: The sum or the product of all digits in a cage is 20. Which cages sum and which cages multiply to 20 must be deduced. Digits can repeat in cages if allowed by the other rules.
- Diagonal: The digits on the postitive diagonal (marked by an arrow outside the grid) either sum or multiply to 20. Which of the cases is true must be deduced.