Pi Sudoku 2020-Deprecated

Edited on 2021/09/10

Here is the reworked version: pi-sudoku-2020-reworked. Please play that version instead.

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RULES

1. Basic Sudoku Rules applied.

2. Clues outside the grid are the sum of digits along the diagonal line (digits along the line may repeat).

3. The gray tubes are thermometers, digits along the thermometers must increase, bulbs contain the minimal value.

4. You can assume that the puzzle has a unique solution.

Edited on 2020/05/31

1. Adjusted the position of clues outside the grid to make them more clear.

2. Removed clue 20, and add clue 17, which makes the solving path more reasonable.

Edited on 2021/01/06

1. Add "RULE 4" to allow solvers using "unique solution" related techniques.