Strategies for Number Puzzles of all kinds
Print Version
Latest Apps


Post an idea here...
Your Name or Handle

Your comment, idea or question

Please enter the
letters you see:
Enter these letters
Remember me

Please keep your comments relevant to this puzzle.
Email addresses are never displayed, but they are required to confirm your comments. To state your solve time use the smaller form at the top right of this page." & vbNewLine & _ Line breaks and paragraphs are automatically converted ? no need to use <p> or <br> tags.

Friday 4-Dec-2020

... by: Cenoman

1. Basics: +5G1, +7G3
2. JE2(1234)G89, H6, J2
Eliminations -19H6, -4J1, -9H45
The puzzle is in hardest ones (S.E. 10.4). The JE doesn't solve it alone but I'd not say it doesn't help at all. At that point it is rated S.E. 9.4. Andrew's solver "ROOKS". My own solver solves it, with a number of complex nets (that I will not post)

Another way to use the JE: directed T&E. Just try the possible pairs of true base digits:
+12G89 =>contradiction (with basics)
+13G89 =>contradiction (with basics + 1 AIC)
14 is an incompatible base pair (1 and 4 can be true only in target J2)
=>1 is a false base digit; -1G89, -1J2, -1H45

S.E. rating is now 9.0 and the puzzle is solved by a sequence of AIC's and krakens (also solved by Andrew's solver)

Tuesday 1-Dec-2020

... by: Kim Uildriks

After eliminating the obvious - using a 'probability' approach C1 = 4, G4 = 8 will solve

Monday 30-Nov-2020

... by: numpl_npm

5G1 7G3

With DFC(Digit Forcing Chains) only,
  6E1(∵6D1 contra.)
  8D1(∵8C1 contra.)
  4C1(∵4C9 contra.)
  4A7(∵4A9 contra.)
  Then to the end.

This puzzle is SE 10.4, but it's difficult.
Exocet does not help with this puzzle.

Sunday 29-Nov-2020

... by: Frans Goosens

With trial and error

Combination B1=239 and G8=123

B1=2 G8=1 No solution, Fixed

Combination 2-digits cells

A6=3 No solution, Undo calculation
A6=5 Wrong, Undo calculation
A6=3 No solution, Fixed
B4=7 Wrong, Undo calculation
B4=9 Wrong, Undo calculation

All reset to initial position

B1=2 G8=2 Wrong, Undo calculation

All reset to initial position

B1=2 G8=3 No solution, Fixed

Combination 2-digits cells

A6=3 Wrong, Undo calculation
A6=5 ( B9=3 ) Solved,

100 200 000-------------139 285 476
065 004 800-------------265 974 813
070 006 900-------------478 316 925

004 000 000-------------894 752 361
050 008 700-------------653 148 792
700 030 040-------------712 639 548

000 000 600-------------527 891 634
080 000 057-------------981 463 257
006 507 089-------------346 527 189

Total solving time is : 190 sec.
Number of logical steps is : 16203

Saturday 28-Nov-2020

... by: James Havard

Top box row 118 subs 134 secs A2=3 with B1=2 for a singles solution.
Middle box row 21 subs 31 seconds D9=1 with E9=2 for a singles solution.
Bottom box row 171 subs 191 seconds G6=1 with H7=2 for a singles solution.


Each week a new 'unsolvable' will be published and the previous will be accessible here from this archive section. If you like very tough puzzles, these are for you.
Share and Enjoy

Page created on 03-May-2011, last modified on 21-Nov-2019.
All puzzles on this site are trademarked and copyright
and cannot be reproduced without permission.
Copyright Syndicated Puzzles Inc, 2011-2019