Logic Masters Deutschland e.V.

Heat death of the Universe

First, the puzzle:

...and now the rules: Normal Irregular Sudoku rules apply. That is, each row, column, and thick-bordered box contains the digits 1-9 exactly once each. Also, there are 5 ‘galactic thermos' in the grid, situated in irregular star-shapes (i.e., pentagrams) and involving 5 cells each. Their digits must strictly increase, starting anywhere and proceeding in any star-shaped sequence, quasi-clockwise or quasi-counterclockwise.

The inequality symbol indicates that R3C6 has a higher digit than R4C6.

For the color-vision-impaired — or those needing an example sequence — the thermos span the following cells, reading from the leftmost and going quasi-clockwise along one possible star pattern:

• bluish: R6C1 R2C6 R8C5 R1C2 R5C8
• magenta: R7C1 R6C6 R9C3 R5C4 R9C5
• pale red: R9C1 R1C6 R9C7 R4C2 R5C9
• gold: R5C3 R5C7 R7C4 R3C5 R7C6
• green: R2C4 R3C9 R5C5 R1C7 R6C8

F-puzzles link, with a thermometer in place of the inequality symbol.

The same in penpa, with built-in solution checking.

Version without colors.

For clarity's sake here are a few more example star patterns with valid digit configurations: