Sudoku Teaching Assistant                                                            Sudoku Patterns List

Sudoku Pattern: Hidden Singles

In this basic pattern, one looks for a row, column or box where a candidate occurs in only one cell.  One first determines the candidates for all the cells in the row, column or box of interest.  Use paper and pencil to do this, or in Sudoku Teaching Assistant, select the row, column or box using the mouse or keyboard and click on the   Show Candidates  button.

If a candidate occurs on only one cell in a row, column or box, then the solution to that cell must be that candidate since the row, column or box must contain every number from 1 to 9.

In the example below, the cell on row 5, column 5 (shown in green) can have only the value 5, because '5' occurs on row 5 only in this cell.  Thus '5' is the solution to this cell.

Sudoku-Help: Naked Single Pattern



In the example below, the cell on row 1, column 7 (shown in green) can have only the value 7, because '7' occurs on column 7 only in this cell.  Thus '7' is the solution to this cell.

Sudoku-Help: Naked Single Pattern


In the example below, the cell on row 7, column 6 (shown in green) can have only the value 4, because '4' occurs in the 'bottom middle' box only in this cell.  Thus '4' is the solution to this cell.

Solve Sudoku: Naked Single Pattern