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Mogulmeister · Joined: 03 May 2007 Posts: 1151

Noodling about the bivalues I found an interesting (to me) almost ALS xz
A={3,8}r5c6 (Green)
B={1,2,3,6,7,8} r12567c9 (Orange)

"restricted" common x=3 and z=8 (Blue) so r5c8<> 8 solving the puzzle.

Unfortunately, there is a fly in the ointment, a fin that breaks up the restricted common, a 3 in r6c9 (Pink) and spoils the ALS xz.

But if the "fin" is true then r5c9<>3 and <678> XY Wing is born, vertex in r1c9 and r5c8<>8.

=======================================

Diversion:

Actually, this is a case of a fin knocking out another fin.

As we have seen there is a fin 3 for the ALS xz in r6c9. There is also a 3 just above it in r5c9 which is the fin of an almost xy-wing. We've seen what happens when it is not true (above) but even if it were:

(68=3)r5c9-(3=8)r5c6-(8)r5c8 ie r5c8<>8 - solved.

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

Looking at possible remote pairs, this different xy-chain...

tlanglet · Posted: Thu Jul 01, 2010 1:31 pm Post subject:

How about an Almost xy-wing 67-8 with vertex (67)r1c9 and fin (3)r5c9
If xy-wing true: r3c9,r5c8<>8
||
(3)r5c9 - (3=8)r5c6; r5c8<>8

Ted

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

Mogulmeister · Joined: 03 May 2007 Posts: 1151

That's the same one I described Ted. Smile

tlanglet · Posted: Thu Jul 01, 2010 1:40 pm Post subject:

MM,

Your dealings with ALS_XZ are amazing Exclamation

I think a "finned Almost" pattern may be a new high.

Ted
(Note: Your ALS_XZ also contains a ANP(38=6)r5c69 - (6=7)r1c9 - (7=8)r3c8; r5c8<>8 which also contains the Almost xy-wing I posted.)

ronk · Joined: 07 May 2006 Posts: 398

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Luke451 · Posted: Thu Jul 01, 2010 2:31 pm Post subject:

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Isn't an ANP (Almost Naked Pair) also an ALS ?

Luke451 · Posted: Fri Jul 02, 2010 5:03 am Post subject:

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Hi Luke, I tend to think in Linnaen taxonomic terms about this: ALS is genus and AN(PQT) is species.

I do however, sympathise with your viewpoint - I feel much the same about the various M/W wings because these days I tend to see AICs.

However, for tyros like me they are useful little hooks to help us on our way even if I no longer remember the difference between the lesser and greater spotted woodpecker. Razz

Incidentally it is still your (and Ted's) fault for getting me into these almost thingys.......... Laughing

keith · Posted: Fri Jul 02, 2010 6:40 am Post subject:

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

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Incidentally Keith

Nearly all My moves in the almost realm have involved fins in cells with at least 3 candidates and are usually based on deviants from patterns.

Mogul (a hybrid guy)

Mogulmeister · Joined: 03 May 2007 Posts: 1151

Diversion on T&E

Can those of us that tinker with our solve paths be said to be indulging in a form of T&E ?

I don't really care about the answer to be honest(ie if you do or don't) but the philosophy is -erm- interesting.

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

I certainly often "optimize" my solve path - sometimes for interesting moves, sometimes for minimal moves. (If I am doing one in the Newspaper on the Tube I take anything I can find!) Suppose it is T&E to some extent, though you can often see immediately that some moves are not going to be very helpful - hidden UR moves almost always do nothing (for me!) - and some that are - say they create a locked set etc.

Like you I'd consider my general approach a hybrid one with a large dollop of laissez-faire.