Clueless Sudoku

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.