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Tough Sudoku for 15/October/2011


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Sudoku Solving Techniques

Submitted by: sudoku lover

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T-Lite 8.5 (SE @ 13K x 8FC)
15/Oct/11 12:10 AM
site puzzle, beginner level 7.2
15/Oct/11 12:13 AM
site puzzle: SSTE
// ext. als-xz:(7=148)dhi4-(4=137)def5-(3)f6=g6 # -7g56.h5.e4
15/Oct/11 12:28 AM
15/Oct/11 12:32 AM
1. Unique possibilities to 33.
2. Whether d8=4;OR f8=4,e8=5=b4,d4=4;d5=13.
3. Whether d5=1,d7=8;OR d5=3=g6,g2=8=d1,g7=1;d4=4.UP81.
15/Oct/11 1:44 AM
Should read ....d7=1...(not g7=d1), in step 3.
15/Oct/11 1:50 AM
Hi Kobold,
A beautiful inovative 1 step solution. Without the ALS-XZ extension, other moves are required to solve the puzzle.
Regards, Bud
15/Oct/11 2:06 AM
Enjoy your weekend, everyone!
15/Oct/11 3:46 AM
T-Lite 8.5
#1 aahs(18)de8,a8,g8 ; d8<>27
(8)a8 - (8=291)a31b1 - d1=d8
(8)g8 - g5=e5 - (8=1)e2 - d1=d8
// w-wing-ish (5=47)h89-f9=d7-(7=5)b7 ; b8<>5,g7<>5
// als-xz (8=147)ach9 - (7=1458)degh8 ; a8<>8
#2 (3=278)f79d7 - More...
15/Oct/11 4:10 AM
T-Lite 8.5 reverse path of peterj:
1. aals(45.78)gh8 # -4a8, -5b8, -8e37.g4
{ (45)gh8-(4=18)e28-(8)e5=g5 }x - (8)i4=MR(94)i4/h652.i2 }y
(7)g8-h9=h2 - y
(8)g8 - x
2. (7=2)b8-(2=8)a8-(8=129)a13b1-(1)d1=d8 # -27d8, SSTE
// als:ahs-xz (7=4)h9-ac9=(457')b78c7 # -7g8
15/Oct/11 5:10 AM
omitted SS(8) as final pattern for T-Lite.
15/Oct/11 5:51 AM
note: the aals is an introvert. Deductions arise from the loop, not the end points. The chain fragment:
{ (45)gh8-(4=18)e28-(8)e5=g5 }
is a stand-alone loop because of weak links x and y. Also, using (8)g8 one sees, because of y:
15/Oct/11 5:58 AM
A smile & a tear!!
15/Oct/11 8:28 AM
bonus round - T-Lite 8.5 II (SE @ 11K x 16FC)
15/Oct/11 9:12 AM
kobold, I followed your logic for the site puzzle, and after g3=7, could only reach UP41. Don't you need another step to finish it?
Regards, Alfred.
15/Oct/11 10:49 AM
try again Alfred. You clearly missed a hidden or naked set elim - I didn't omit any SSTE pattern.
15/Oct/11 12:04 PM
T-Lite Bonus
// m-wing(71) a2,e26,ec6 ;c12<>1
// m-wing(71) a2,e26,e6d5 -d1=i1 ; h2<>1
#1 (48=3)h52 - c2=c1* - (7)c1=f1 - e2=(7-1)e6=d5 - d1=i1 - *(9)ci1=g1 - (9=8)g6 ; h6<>8
#2 (3)g1=(3-4)g9=e9 - (4=138)e3d13 ; f1<>3
15/Oct/11 7:44 PM
Hi kobold,

Almost Locked Sets are not in the Simple Sudoku Technique Set, so your assertion of SSTE is mistaken.
15/Oct/11 8:53 PM
You're right kobold, Neil pointed out a 389 triple I missed.
15/Oct/11 9:10 PM
Thank you for your solution to the T Lite Bonus round. I completely missed the inherent power of eliminating (3)f1!
15/Oct/11 10:18 PM
Kobold, I was pleasantly surprised too! I tend to focus on eliminations that break or make strong links or bivalues - at least as a first cut. This one gets it strength from exposing a triple rather than anything to do with 3s
15/Oct/11 10:42 PM
another way for T-Lite II:
// MW(71)a2/e26.c6, -1c12
// ext. MW(71)a2/e26.d51.i1, -1hi2
1. aals(348.19)i239 # -3h2, SSTE
// SDQ(134689)d138.e389, -6f8,-14e2,-8f123.d5
// YW(17.6)a29.e2, -6e9
15/Oct/11 11:03 PM
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