Normal sudoku rules apply. Digits on a blue line must have an equal sum N within each 3x3 box the line passes through. If a line re-enters a 3x3 box, each segment sums to N separately. eg r3c1+r3c2=r4c2=r3c3+r2c3=r2c4=r1c2+r1c3
Normal sudoku rules apply. Digits on a blue line must have an equal sum N within each 3x3 box the line passes through. If a line re-enters a 3x3 box, each segment sums to N separately. eg r3c1+r3c2=r4c2=r3c3+r2c3=r2c4=r1c2+r1c3