7 Cell Swordfish Patterns

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In the example below, the Column Pairs form highlights a 7 cell swordfish pattern, see rectangle. In this case 3 rows have been highlighted as having 2 or 3 cells aligned by columns. In sudoku parlance, a 6 can only occur in the swordfish pattern rows, A, H & I at columns 2, 5 & 7. This means all other 6's in those rows can be removed: A4, A6, A8, H6, I4, I6 & I8.

After clearing the target digit, the 6 numeric button needs to be clicked again to refresh the Column Pairs for further inspection.