Nineteen is a prime number, and we're primed to present #19 in our Pocket Posh Sudoku series offering 100 fun and challenging Sudoku puzzles in three levels of difficulty. Pocket Posh Sudoku 19 is perfect for puzzlers looking for a quick and engaging puzzle to complete. This portable package is part of a best-selling series featuring highly stylized, embellished covers and boasting 5 million copies in print.