Switch-engine 'bobsled run'
The reaction is unusual for several reasons:
1) Tub-with-tails don't usually catalyze alone -- a tub-with-tail is more commonly paired with a block or other still life, which makes it capable of 'eating' a glider or similar active pattern.
2) The catalysis used in the bobsled run is a reaction that has not been used in previously known Herschel/B-heptomino/R-pentomino/pi conduits.
3) While Herschels do make an appearance in this conduit, they don't play an important role -- in fact, they must be suppressed in order for the reaction to be repeatable.
One possible open problem would be to construct converters to attach to each end of the 'bobsled run', one taking a Herschel (or glider, spaceship, etc.) as input, and one producing one of these standard signals as an output.
New Period 24 Oscillator
Jason Summers has found a new Period 24 Oscillator. The Heavyweight Emulators at the top and bottom can be replaced by other P4 or P6 oscillators at the expense of symmetry, producing slightly smaller objects.
New Compact Corderships
David Bell has constructed a new, compact 5-engine Cordership that contains a releasable sideways glider, and has compiled a series of related results. The pattern at the far right shows a number of ways for the Cordership's northeast edge blocks to be suppressed, allowing the sideways glider to escape.
These new results build on other new Cordership constructions recently -- in particular, a small 3-engine Cordership discovered by Paul Tooke (with the help of Paul Callahan's handy 'gencols' utility) on January 12 of last year. David Bell discovered that it can turn an LWSS 90 degrees, as shown here.
Bell has also produced a series of related Cordership-rake patterns:
A Cordership-based glider-to-backward-LWSS reaction
A 'beehive-puller' Cordership
A p96 forward glider rake
A new smaller p384 'Freeze-Tag' spaceship
A reaction converting two forward gliders to an HWSS
p192 backward HWSS rake
A p96 backward HWSS rake
A p768 backward HWSS rake
A p96 forward LWSS rake
A p96 forward MWSS rake
An alternate p96 forward MWSS rake
A p768 forward LWSS rake
A high-period Cordership-based feedback loop
A wide thin p96 backward rake
A p288 'litterbug' spaceship
A p96 backward LWSS rake
An alternate p96 backward LWSS rake
A p96 backward MWSS rake based on a loaf puffer
A backward LWSS puffer based on an eater/tub-with-tail puffer
Related to this last pattern, he notes that a line of tub-with-tails "can support one side of a switch engine without being modified. Two diagonal lines of them can support one or more switch engines at the ends, and one line can support a 3-engine wing component."
Update: 24 June 2005 2:20pA diagonal c/12 p96 glide-symmetric double backward rake
A p96 three-stage tail producing a double-backward-rake spaceship
A p96 block-staircase puffer tail for the double backward rake
A p96 diagonal c/12 period 96 sideways glider-inserter rake
... And an updated version of Jason Summers' c/12 p96 diagonal lineship: see the new posting on this subject.
Extensible Wickstretcher-like Spaceship
Hartmut Holzwart has found a Lightweight Spaceship convoy which consists of a Period 4 wickstretcher head, a Period 19 wick and a Period 4 fuse. Shown is the simplest version with only one copy of the wick and one with two copies of it. (Note that there are no known Period 19 oscillators, so finding stable ends for this wick may take a while, but it could be the foundation for such an oscillator.)
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