Here is a variant of clueless Sudoku that I was trying for fun. In clueless Sudoku
- A n*n board is given
- No numbers are written on the board
- The board is divided in some blocks (typically in some pattern). Sum of numbers in each block must be constant.
- Numbers 1 to n must appear in each row and each column with out repetition.
Consider the following example:

The red bordered boxes should have the same sum of numbers as the remaining boxes. No number should repeat in a row or a column.