... by: Norman Powell
A few more eliminations through Forcing Networks otherwise unsolvable.Read from bottom and rows numbered, columns lettered:
Forcing Networks Value 2 in Row 1 Column H cannot be ON so eliminate
Contradiction: No possibilities left for Row 1 Column D
Forcing Networks Value 2 in Row 1 Column E cannot be ON so eliminate
Contradiction: More than one Value 7 ON in Column G
Confined to Box Value 6 is confined to Column A and Box 1.
Forcing Networks Value 6 in Row 7 Column A cannot be ON so eliminate
Contradiction: More than one Value 4 ON in Row 7
Forcing Networks Value 4 in Row 1 Column G cannot be ON so eliminate
Contradiction: More than one Value 5 ON in Row 9
Forcing Networks Value 5 in Row 5 Column F cannot be ON so eliminate
Contradiction: More than one Value 4 ON in Box 4
Forcing Networks Value 4 in Row 5 Column A cannot be ON so eliminate
Contradiction: More than one Value 3 ON in Row 6
Forcing Networks Value 5 in Row 8 Column B cannot be ON so eliminate
Contradiction: More than one Value 5 ON in Column I
Hidden Singles In Column 9 I2 = 8.
Forcing Networks Value 8 in Row 8 Column I cannot be ON so eliminate
Contradiction: More than one Value 1 ON in Column I
Forcing Networks Value 4 in Row 9 Column G cannot be ON so eliminate
Contradiction: More than one Value 9 ON in Row 5
Hidden Pairs Hidden Pair in Box 6, for Values: 1 3 in Cells: I4 H6