Sawtooth 177
Sawtooth 177 | |||||
View static image | |||||
Pattern type | Sawtooth | ||||
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Number of cells | 177 | ||||
Bounding box | 68 × 77 | ||||
Discovered by | thunk | ||||
Year of discovery | 2015 | ||||
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Sawtooth 177 is a refinement of Sawtooth 181 obtained by rephasing the constituent guns. It is the smallest known sawtooth in terms of its minimum repeating population of 177. An bounding-box-optimized variant, Sawtooth 189, has a repeating population of 189 and a bounding box of 63x57,[1], significantly smaller than the previous 79x55 record set by Sawtooth 201.
The sawtooth functions by letting two glider streams of period 120 retract a block, created by collision with a spark from a 58P5H1V1, one cell at a time. The retracted block is deleted via interaction with a pentadecathlon, and the streams are allowed to return to the now-farther-away 58P5H1V1 to create another block.
Population
The population is equal to 177 at generations 0, 5760, 702720, 85034880, ..., 48 * (121^n - 1), ..., giving an expansion factor of 121.
References
- ↑ thunk [pseudonym] (October 31, 2015). "Re: Smaller sawtooth". Retrieved on October 31, 2015.