Number puzzles online Bricks 7x7 #1 Light (another name is Bricks, Brick Sudoku)
It is a type of 2d sudoku. Available mesh sizes are 6x6, 7x7, 8x8, 9x9.
This puzzle option has additional conditions:
In the cells of each “brick” one digit is even, the other is odd. Two halves of the “brick” located at the edge of the puzzle form one “brick”. The task is to enter the numbers from 1 to N in the puzzle cells so that in each horizontal row, in each vertical column, each number occurs only once.