Logic Masters Deutschland e.V.

The puzzle is based on a shared idea by Burning Curtains and me and can be seen as a twin to his fantastic puzzle "Squares and Circles" .

More information about my Double Trouble series as well as links to the other puzzles of the series can be found below the puzzle.

Rules:

Sudoku: Fill every row, column and 3x3 box with the digits 1-9.

Killer: In cages digits must not be repeated an have to add up to a square number (1, 4, 9, 16,...).

Hidden Double Trouble: There are 9 cells in the grid that contribute their double value to the cage total. Those cells need to be determined by the solver. The 9 cells follow the rules of sudoku (i.e. place exactly one doubling cell in each row, column and 3x3 box) and each of the digits 1-9 have to appear once in them. Cages must not contain more than one double counted cell.

Inequality: The inequality sign indicates that r5c5 contains a higher digit than r4c5.

Have fun solving!

Sudoku on:
f-puzzles
CTC-App

The Double Trouble series:
It's a simple idea. Treat a few cells as if they are double their value. But it has tons of interesting logic and can turn known rule variations completely upside down. With this series I want to show this diversity.

Variant introduction: Easy to moderately difficult puzzles that show the combination of doubling cells with different variants.
Double Trouble - Arrows
Double Trouble - Killer
Double Trouble - Skyscraper

I look forward to any feedback and suggestions about the series.