[r-t] All runs in a quarter, proper version!
Alexander Holroyd
holroyd at math.ubc.ca
Fri Jan 30 10:26:40 UTC 2015
There was a mistake in the p.n. for the Block A line. Here it is.
http://www.boojum.org.uk/cgi-bin/line.pl?bells=8&pn=56-4.56.1.56.1.34.5-36.5.34-4.3.6-56-5.34.1.34.5-5-3.4.3.56-5-1-4-34.6.5.6-4-4.56.1.56.4-34-3.6.5-56.4.36-4.56.1.34.1.34.5-34&qs=Line&action.x=1
On Fri, 30 Jan 2015, Alexander Holroyd wrote:
> On Fri, 16 Jan 2015, Philip Earis wrote:
>
>> As the overall aim here is to get all 480 run rows, I’m tempted to
>> generalise and rephrase accordingly...what’s the shortest length 8-part
>> anyone can produce which contains all 480 runs? Elegance and maximal
>> symmetry are desirable.
>>
>> Posing the question like this lends itself to interesting architectured
>> approaches...previous 480-run solutions (whilst superb) have applied
>> traditional constraints such as consisting of a number of different,
>> treble-dominated methods.
>
> Thanks for this challenge, Philip. After considerable effort I believe I
> have a good solution. All 480 runs (including 1234s this time) in a longish
> quarter length (3.2 runs per row on average!). 16-part structure plus exact
> rotation symmetry. At most a 2-row gap between "potential runs" (including
> things like 7812). No long places. No single or double changes. Lots of
> variety in run types, and lots of movement across 45.
>
> Also the simplicity and obvious structure make it the perfect thing for any
> fledgling band to toss off on the way to the pub.
>
> 1536 Major
> Alexander E Holroyd
>
> 12345678
> ------------
> x 34562871 )
> 18 35426781 )A
> z 45678123 )
> ------------
> 2A 23456781
> ------------
> x 45673182 )
> 38 54637812 )
> y 65437281 )B
> 16 64573218 )
> z 54321876 )
> ------------
> x 32184675 )
> 38 23148765 )
> y 12348576 )
> 36 21384567 )C
> y 32184756 )
> 16 31248765 )
> z 21876543 )
> ------------
> 6C 87654321
> ------------
> B 56781234
> ------------
> 4A 12345678
> ------------
>
> x = 56-4.56.1.56.1.34.5-36.5.34-4.3.6-56-5.34.1.34.5-5-3.4.3.56-5-
> y = 4-4-6.3.56.34.1.34-5.4-56.1.56.34.6.3-5-5
> z = -4-34.6.5.6-4-4.56.1.56.4-34-3.6.5-56.4.36-4.56.1.34.1.34.5-34
>
> Blocks A, B and C each have rotational symmetry
>
> 24 each 1234s, 2345s, 3456s, 4567s, 5678s, forwards and backwards, front and
> back (3.2 rows per run!)
>
>
> Block B grid:
>
> http://www.boojum.org.uk/cgi-bin/line.pl?bells=8&pn=56-4.56.1.56.1.34.5-36.5.34-4.3.6-56-5.34.1.34.5-5-3.4.3.56-5-3.4-4-6.3.56.34.1.34-5.%204-56.1.56.34.6.3-5-5.6-4-34.6.5.6-4-4.56.1.56.4-34-3.6.5-56.4.36-4.56.1.34.1.34.5-34&title=Block%20B&qs=Grid&lines=1&line=2&line1=a&line2=n&style=1&place-bellsx=on&miss-numbers=never&rule=36%3B61&action.x=1
>
> Block A line:
>
> http://www.boojum.org.uk/cgi-bin/line.pl?bells=8&pn=56-4.56.1.56.1.34.5-36.5.34-4.3.6-56-5.34.1.34.5-5-3.4.3.56-5.1.-4-34.6.5.6-4-4.56.1.56.4-34-3.6.5-56.4.36-4.56.1.34.1.34.5-34&title=Block%20A&qs=Line&action.x=1
>
>
>
>
>
>
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