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Thanks for your solutions.
I chose this puzzle because it can be solved without any impossible pattern other than tridagon, but using some reduces the rating.
Here's a solution with two impossible patterns, starting from the RS after whips[1]:
naked-triplets-in-a-column: c2{r2 r6 r8}{n9 n5 n1} ==> r7c2≠9, r7c2≠5, r7c2≠1, r5c2≠9, r4c2≠9, r3c2≠9, r3c2≠5, r3c2≠1, r1c2≠9, r1c2≠5, r1c2≠1
singles ==> r7c2=4, r4c3=4
The impossible patterns used:
- Code: Select all
Trid-OR2-relation for digits 1, 5 and 9 in blocks:
b1, with cells (marked #): r1c1, r2c2, r3c3
b3, with cells (marked #): r1c9, r2c8, r3c7
b7, with cells (marked #): r9c1, r8c2, r7c3
b9, with cells (marked #): r9c7, r8c8, r7c9
with 2 guardians (in cells marked @): n2r1c1 n3r2c8
+----------------------+----------------------+----------------------+
! 1259#@ 26 3 ! 1459 24569 12469 ! 7 8 159# !
! 4 159# 7 ! 1359 8 139 ! 2 1359#@ 6 !
! 12589 268 159# ! 1359 235679 123679 ! 159# 1359 4 !
+----------------------+----------------------+----------------------+
! 2389 278 4 ! 6 379 5 ! 189 129 139 !
! 2389 278 6 ! 349 1 3479 ! 589 259 359 !
! 1359 159 159 ! 2 39 8 ! 6 4 7 !
+----------------------+----------------------+----------------------+
! 6 4 159# ! 8 259 129 ! 3 7 159# !
! 7 159# 8 ! 1359 3569 1369 ! 4 159# 2 !
! 159# 3 2 ! 7 459 149 ! 159# 6 8 !
+----------------------+----------------------+----------------------+
EL14c30-OR4-relation for digits: 1, 5 and 9
in cells (marked #): (r2c2 r3c8 r3c7 r3c3 r1c4 r1c9 r1c1 r9c7 r9c1 r7c9 r7c3 r8c4 r8c8 r8c2)
with 4 guardians (in cells marked @) : n3r3c8 n4r1c4 n2r1c1 n3r8c4
+----------------------+----------------------+----------------------+
! 1259#@ 26 3 ! 1459#@ 24569 12469 ! 7 8 159# !
! 4 159# 7 ! 1359 8 139 ! 2 1359 6 !
! 12589 268 159# ! 1359 235679 123679 ! 159# 1359#@ 4 !
+----------------------+----------------------+----------------------+
! 2389 278 4 ! 6 379 5 ! 189 129 139 !
! 2389 278 6 ! 349 1 3479 ! 589 259 359 !
! 1359 159 159 ! 2 39 8 ! 6 4 7 !
+----------------------+----------------------+----------------------+
! 6 4 159# ! 8 259 129 ! 3 7 159# !
! 7 159# 8 ! 1359#@ 3569 1369 ! 4 159# 2 !
! 159# 3 2 ! 7 459 149 ! 159# 6 8 !
+----------------------+----------------------+----------------------+
EL13c179-OR4-relation for digits: 1, 5 and 9
in cells (marked #): (r3c4 r3c7 r3c3 r2c4 r2c8 r2c2 r9c7 r9c1 r7c9 r7c3 r8c4 r8c8 r8c2)
with 4 guardians (in cells marked @) : n3r3c4 n3r2c4 n3r2c8 n3r8c4
+----------------------+----------------------+----------------------+
! 1259 26 3 ! 1459 24569 12469 ! 7 8 159 !
! 4 159# 7 ! 1359#@ 8 139 ! 2 1359#@ 6 !
! 12589 268 159# ! 1359#@ 235679 123679 ! 159# 1359 4 !
+----------------------+----------------------+----------------------+
! 2389 278 4 ! 6 379 5 ! 189 129 139 !
! 2389 278 6 ! 349 1 3479 ! 589 259 359 !
! 1359 159 159 ! 2 39 8 ! 6 4 7 !
+----------------------+----------------------+----------------------+
! 6 4 159# ! 8 259 129 ! 3 7 159# !
! 7 159# 8 ! 1359#@ 3569 1369 ! 4 159# 2 !
! 159# 3 2 ! 7 459 149 ! 159# 6 8 !
+----------------------+----------------------+----------------------+
naked-quads-in-a-row: r3{c3 c8 c4 c7}{n9 n5 n3 n1} ==> r3c6≠9, r3c6≠3, r3c6≠1, r3c5≠9, r3c5≠5, r3c5≠3, r3c1≠9, r3c1≠5, r3c1≠1
EL13c179-OR4-relation between candidates n3r3c4, n3r2c4, n3r2c8 and n3r8c4
+ same valence for candidates n3r2c8 and n3r3c4 via c-chain[2]: n3r2c8,n3r3c8,n3r3c4
==> EL13c179-OR4-relation can be split into two EL13c179-OR3-relations with respective lists of guardians:
n3r3c4 n3r2c4 n3r8c4 and n3r2c4 n3r2c8 n3r8c4 .
EL13c179-OR3-whip[1]: OR3{{n3r8c4 n3r2c4 n3r3c4 | .}} ==> r5c4≠3naked-triplets-in-a-block: b1{r1c2 r3c1 r3c2}{n6 n2 n8} ==> r1c1≠2
At least one candidate of a previous Trid-OR2-relation between candidates n2r1c1 n3r2c8 has just been eliminated.
There remains a Trid-OR1-relation between candidates: n3r2c8
Trid-ORk-relation with only one candidate => r2c8=3hidden-single-in-a-block ==> r3c4=3
At least one candidate of a previous EL14c30-OR4-relation between candidates n3r3c8 n4r1c4 n2r1c1 n3r8c4 has just been eliminated.
There remains an EL14c30-OR1-relation between candidates: n4r1c4
EL14c30-ORk-relation with only one candidate => r1c4=4The end is trivial, in BC3.
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