[r-t] Exhausted search spaces
richard at ex-parrot.com
Thu Feb 4 20:54:45 UTC 2010
David Sullivan wrote:
>> But I cannot believe that this was done "many years ago" and
>> the suggestion that the results were printed out is clearly
> Yes. This was over thirty years ago and my memory of the
> exact wording is obviously hazy.
Maybe he was looking for a perfect three-part? Modulo
rotations, there are 4 such extents of Cambridge Minor and
1770 of Plain Bob Minor.
> ISTR him saying that the first extent that was produced started with
> 5 homes, the program presumably being written to favour plain leads
> over calls. He was rather pleased to announce that the real basic
> extent of PB6 was this one, starting with 5 homes followed by a
> nightmarish mishmash of pseudo-random plains, bobs and singles.
That sounds very plausible. My search program does
precisely the same. The first extent of PB6 it finds is:
(where a . is a plain lead).
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