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keith · Posted: Sat May 28, 2011 1:32 am Post subject: Free Press May 27, 2011

I have done this one.

Marty R. · Posted: Sat May 28, 2011 4:25 am Post subject:

I didn't read your hint before I did it, but I did have two VH steps.

XYZ-Wing (157); r3c3<>7
XY-Wing (257); r3c7<>7

keith · Posted: Sat May 28, 2011 7:19 am Post subject:

Marty,

Yes. There is lots of variability in the difficulty of these Friday Freep puzzles.

For this one, my notes say: XYZ 15-7; XY 25-7. Which looks like the same solution as yours.

Keith

peterj · Joined: 26 Mar 2010 Posts: 974 Location: London, UK

There's also a swordfish(7) that makes the same elimination as the xyz - and a few more

tlanglet · Posted: Sat May 28, 2011 1:54 pm Post subject:

Box3 and row3 has an interesting pattern of four cells that makes the identical elimination, r3c7<>7, viewed in four different ways……

#1: axy-wing(25-7) with vertex (25)r3c8 and fin (3)r3c6
If fin is true: (3)r3c6-(3=7)r3c3;

#2: (7=5)r1c9-(5=2)r3c8-als(2=37)r3c63;

#3: anp(37=2)r3c36-(2=5)r3c8-(5=7)r1c9;

#4: als_xz
als A=(57)r1c9
als B=(2357)r3c368
x=5
z=7

Ted