The New Sudoku Players' Forum

[Eioru]

Code: Select all

 
..4368975
738..52.6
59627..38
9675.3.82
.4578.369
8.36..5.7
.528.7691
681...75.
.7915682.


It has 2 Unique loops of a{1,2}andb{3,4}... so rare ...

Code: Select all

 
aa4368975
738..52.6
59627..38
9675.3.82
a4578a369
8a36.a5.7
b528b7691
681.b.75b
b7915682b


and I try to delete c{5,6} to make Unique loops like

Code: Select all

..43c897c
738..c2.c
59627..38
9675.3.82
.4578.369
8.36..5.7
.528.7691
681...75.
.791cc82.


But can't use...

[Eioru]

How to make a puzzle must need using UL(UniqueLoop) or UR more than 3 times when solving it?