15- Repeated Diagonals

Repeated Diagonals

(Published in Czech Republic Championship)

Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each row, column and 3x3 box. Moreover, there are some shaded cells in the grid which the number in such cells indicate how many times that number is repeated (other than itself) in that cell diagonals.

14- X-Sums Sudoku

X-Sums Sudoku

(Published in Czech Republic Academic Championship)

Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the irregularly shaped regions. The numbers outside the grid represent the sum of the first X digits in the respective row or column, with X being the digit in the first cell of that row or column.

13- Arrow Sudoku

Arrow Sudoku
(Published on SudokuCup.com)

Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each row, column and 3x3 box. The number in a circle is the sum of the digits which are covered by its arrow.

12- Palindrome Sudoku

Palindrome Sudoku

(Published in Daily League! The League of Extraordinary Ladies and Gentlemen & on SudokuCup.com)

Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each row, column and 3x3 box. The digits in the squares with the line form palindromes, i.e. they are read evenly from both sides.

11- Straight Sudoku

Straight Sudoku

(Published in Czech Republic Academic Championship)

Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each row, column and 3x3 box. Moreover, the indicated lines in the grid should contain straight consecutive digits (e.g. 1-2-3-4, not 1-2-3-2!). Where there is no indicated line there can't be any straight horizontal, vertical or diagonal line which contains more than 2 consecutive numbers.