Twin Equivalent Sudokus

[aman]

This sudoku variant also includes the more simple "Twin Corresponding Sudokus".

Twin A



Twin B


Source: Yahoogroup Sudokuworld http://games.groups.yahoo.com/group/sudokuworld/

Rules of Twin Equivalent Sudokus (devised by Henry Kwok)

This Sudoku variant consists of a pair of linked standard Sudoku puzzles each with some starting digits. As usual, the object of this Sudoku variant is to fill in the whole of the 9x9 grid with digits 1 through 9 so that each row, each column and each box contain all the digits 1 through 9.

Twin B is related to twin A in the following ways:

Given that twin A is the original puzzle, twin B can be obtained
1. by rearranging all the digits 1 through 9 so that each digit in twin B corresponds one to one to a digit in twin A,
2. by exchanging a block of rows (columns) with another block of rows (columns) in the same grid.
3. by exchanging a row (column) with another row (column) within the same block of rows (columns) in the same grid.

Twin B can be formed from twin A by one or a combination of the above methods. Both twins are essentially the same or equivalent puzzle.

[aman]

This example devised by Henry Kwok is easier to solve.

Twin A



Twin B