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keith · Posted: Tue Jun 15, 2010 6:02 am Post subject: June 14 BB sh

More than your usual walk in the park:

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Certainly not a usual walk for me.......

1.XY chain on 2s (2=4)r5c3-(4=6)r2c3-(6=4)r2c1-(4=1)r6c6-(1=2)r6c4; r5c4<>2

2. ALS XZ: At r5c7 X={4,7} At r1467c8 Z={1,2,4,7,8}
Restricted common is 4, Common is 7 so r2c7<>7

3. Colouring on 2s exposes a contradiction and r4c2, r5c9, r6c9 and r9c8 <>2

ronk · Joined: 07 May 2006 Posts: 398

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Perfect. I named the sets X and Z and gave no algebraic representation to the common elements because I had already explicitly named them. I shall adopt the convention.

keith · Posted: Tue Jun 15, 2010 8:28 pm Post subject:

Interesting. Most of us pencil and paper solvers have long given up looking for swordfishes ...

Keith

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Interesting.
Who mentioned swordfish ?
The correct plural surely.? Very Happy

keith · Posted: Tue Jun 15, 2010 8:57 pm Post subject:

After basics, and an XY-wing -124:

Mogulmeister · Joined: 03 May 2007 Posts: 1151

I see what you mean.

In my version, I discounted the swordfish on 1s because it didn't have as great an effect as the ALS (which I am more partial to*) and would have meant another step (to solve the puzzle).

You still need more moves of course after the swordfish. Can a jellyfish be found ?

[Ed * In terms of fun!]

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Yes it can!! (I think)
Start with your same first move Keith then instead of sword, LOOK FOR JELLY!!!

R1468C1589 - of course, once the excitement dies down we still only make the same eliminations as the swordfish but hey !?

Marty R. · Posted: Tue Jun 15, 2010 10:22 pm Post subject:

I used five moves, probably not all necessary.

XY-Wing (142)
Kite (1) + extension
Type 6 UR (28)
XY-Wing (128)
Kite (2)