Verifying Sue de Coq Alternatives in Insane 495

This post embarks on the advanced solving of Insane 495, the ninth in a set of 10 puzzles preselected for a review of the KrazyDad  Insane collection on .

So what did you turn up on the Insane 495 line marked grid?

IN 495 two SdCMy first nuggets of logical gold were two hard to verify Sue de Coq in chutes Nr3 and Ec8.

The contents of chute Nr3 we have to describe as 9(4+8)(2+5)+529, because 4and 8 can be missing.  Similarly we describe the contents of Ec8 as 1(3+8)(4+6)+138 , because 4 and 6 can be missing.

The payoff removals of the Sue de Coq chutes are shown. But before the removals, verification comes first.

IN 495 SdC trialsEarlier in the blog I have used trials to verify that Sue de Coq spoiler combinations like 529 and 138 cannot be true.  Both are rejected here, with the  trial traces revealing the difficulty of these verifications.





Ironically, after verifying that 138 cannot be missing, the SdC removes an opposing 4, and the naked pair 46 removes 3 and 8 candidates from the chute.  Krazy.

IN 495 swordfishI had no luck on the bv map, but was rewarded for that 3-candidate removal when I got to the 3-panel .  A very productive swordfish actually splits the 3-candididate cloud into a pair of disjoint, dead swordfish.

I was so taken with the regular 283-wing after so many forcing chained ones, that I left it on the grid.  ER victims could emerge as the fog of 8-candidates disperses.

At  this point, I ran out of advanced solving ideas, and took the extreme route through LPO valley.  Before next post, you can try jumping in line ahead of me by finding an advanced trick I missed.  Or you might plow into LPO with a pink olive analysis. If it helps, I don’t mind hinting that I had to drag in pattern lettering and LPO conflict logic to get results.

I finished the Akron Marathon in 5 hours, 45 minutes, despite a collision with a sidewalk that required eight stitches.  Thanks to Dr. Bullard, my writing hand still works, and I’ll see you on the Insane 495 playing field next time.


About Sudent

My real name is John Welch. I'm a happily married, retired professor (computer engineering), timeshare traveling, marathon running father of 3 wonderful daughters and granddad to 7 fabulous grandchildren. The blog is about Sudoku solving. It covers how to start, basic solving to find candidates efficiently, and advanced solving methods in an efficient order of battle. It is about human solving methods, not computer solving.
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