Pentapole
Pentapole  
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Pattern type  Oscillator  

Family  Barberpole  
Number of cells  11  
Bounding box  8 × 8  
Frequency class  38.3  
Period  2  
Mod  1  
Heat  10  
Volatility  0.63  
Strict volatility  0.63  
Discovered by  MIT group  
Year of discovery  1970  
 
 
 

The pentapole is the barberpole of length 5. It is the eighth smallest of all oscillators, and the only nonpseudo oscillator with a minimum population of 11 cells.
Commonness
The pentapole appears nowhere near as frequently as the bipole, tripole or quadpole, and is nowhere to be seen among the 88 most common oscillators in Catagolue as of February 2022. As of 13 March 2024, it is the 112th most common period2 oscillator in Catagolue.
Much like with the tripole and other barberpoles with diagonal line symmetry, it is much more common in censuses with said symmetries; as of 13 March 2024, it is the 22nd most common period2 oscillator in D2_x, 24th in D4_x1, 27th in D4_x4, 31st in D8_1 and 42nd in D8_4.
It first appeared naturally on March 31, 2015, in a soup submitted to Catagolue by David S. Miller.^{[1]}
Glider synthesis
Mark Niemiec's website lists the pentapole as having a 10glider synthesis as of 2013, using a threeglider component on an existing quadpole to lengthen it by one stage.^{[2]} This has since been reduced to 8 gliders, based on an asymmetric sevenglider collision which produces a pentapole alongside an easily removable boat.
Pentapoleplusboat synthesis (click above to open LifeViewer) 
See also
References
 ↑ gameoflifeboy (April 1, 2015). Re: Soup search results (discussion thread) at the ConwayLife.com forums
 ↑ http://conwaylife.com/ref/mniemiec/p2.htm
External links
 Pentapole at the Life Lexicon
 11P2.1 at Heinrich Koenig's Game of Life Object Catalogs
 Patterns
 Patterns with Catagolue frequency class 38
 Natural periodic objects
 Oscillators with 11 cells
 Periodic objects with minimum population 11
 Patterns with 11 cells
 Patterns found by MIT group
 Patterns found in 1970
 Patterns that can be constructed with 8 gliders
 Oscillators
 Barberpole variants
 Oscillators with period 2
 Oscillators with mod 1
 Oscillators with heat 10
 Oscillators with volatility 0.63
 Oscillators with strict volatility 0.63
 Patterns with bilateral diagonal symmetry
 Flipping oscillators