Sum Sudoku 12x12, 10x10 and 25x25

New: sum sudoku 25x25 (baptized me with the name "Sudoku Sum 65"), sum sudoku 12x12 (baptized by me with the name "Sudoku Sum 26") and sum sudoku 10x10 (baptized by me as "Sudoku Add 9 ". Solved Sudokus sum by sum, but also by logic. Ideal for practicing mind with math and logic.