The New Sudoku Players' Forum

[champagne]

Hi Gordon,

Good to have another path leading to the same conclusion.
This puzzle has a path giving, using efficient sets of rules, to the "loki pattern".

This does not close the door to a better path as experts can do, but it is in line with my "proof".

Cheers

EDIT you are interested in "double THs",
in my work, most of them come as "oddities". I'll keep an eye on such cases

[pjb]

I started out same as Eleven =>

Type 2 unique rectangle of 59 at r38c45, eliminating 1 from r8c36, r9c46, then
type 2 TH with SL between 9 at r4c1 and 6 at r4c6
Simple chain: (9)r4c1 == (6)r4c6 - (6)r4c4 = (6)r9c4 - (6=5)r9c1236 - (5=9)r8c3 => -9 r45c3, r7c1

The resulting grid can be solved in one move using substitution approach as detailed on my website

Phil