Difference between revisions of "Fore and back"

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{{Oscillator|p=2|c=24|name=Fore and back|pname=foreandback|discoveryear=1994|discoverer=Achim Flammenkamp|life105=true|life106=true|plaintext=true|rle=true|animated=true}}
{{Oscillator
'''Fore and back''' (or '''complementary blinker''') is a [[period]] [[:Category:Oscillators with period 2|2]] [[oscillator]] that was found by [[:Category:Patterns found by Achim Flammenkamp|Achim Flammenkamp]] in July [[:Category:Patterns found in 1994|1994]]. It is about the 38th most common naturally-occurring oscillator, being less common than [[boat on spark coil]] and [[griddle and block]], about as common as [[21P2]], and more common than [[trans-block and long hook eating tub]] and [[beacon and long hook|trans-beacon down and long hook]].<ref>{{cite web|url=http://wwwhomes.uni-bielefeld.de/achim/freq_top_life.html |title=Most seen natural occurring ash objects in Game of Life |author=Achim Flammenkamp |date=September 7, 2004 |accessdate=January 15, 2009}}</ref>
|name            = Fore and back
|pname            = foreandback
|f1              = Billiard table
|c                = 24
|bx              = 7
|by              = 7
|fc              = 30.6
|p               = 2
|m                = 1
|h                = 4
|v                = 0.15
|rotor            = Pole 2
|discoverer       = Achim Flammenkamp
|discoveryear    = 1994
|rulemin          = B3/S23
|rulemax          = B3678/S02345678
|rulespecial      = [[Conway's Game of Life|Conway Life]], [[HighLife]]
|isorulemin      = B3y/S2aen3anr
|isorulemax      = B1e2kn34-iry5-nr678/S01c2345678
|synthesis        = 6
|synthesisRLE    = true
|plaintext       = true
|rle             = true
|animated         = true
|viewerconfig    = #C [[ GPS 2 THUMBSIZE 2 ]]
|apgcode          = xp2_ca1n0brz330321
|pentadecathlonid = 24P2.142
}}
'''Fore and back''' (or '''complementary blinker'''<ref>{{CiteLexicon|file=lex_c.htm#complementaryblinker|name=Complementary blinker|accessdate=December 3, 2018}}</ref>) is a {{period|2}} [[oscillator]] that was found by [[Achim Flammenkamp]] on July 12, {{year|1994}}.<ref>{{CiteHickersonOscillators|accessdate=March 14, 2020}}</ref> Its [[rotor]] is the same as the [[blinker]].
 
==[[List of common oscillators|Commonness]]==
Fore and back is about the thirty-eighth most [[common]] naturally-occurring oscillator in [[Achim Flammenkamp's census]], being less common than [[boat on spark coil]] and [[block on griddle]], about as common as [[21P2]], and more common than [[trans-block on long hook eating tub]] and [[trans-beacon down on long hook]].<ref>{{citeAchim|accessdate=January 15, 2009}}</ref> It is the most common oscillator that is generally agreed to be a [[billiard table]], though some instead give this title to the more common [[test tube baby]], which counts under a looser definition.<ref name="post78873" />
 
==Synthesis==
In August {{year|2013}}, a {{gliders|24}} [[synthesis]] of this oscillator was found by [[Martin Grant]], based on a [[soup]] provided by [[Lewis Patterson]]. Several days later [[Mark Niemiec]] improved this result, having found a {{gliders|20|brief}}-glider synthesis.<ref>{{cite web|url=http://www.conwaylife.com/forums/viewtopic.php?p=8688#p8688|title=Synthesising Oscillators|author=Lewis Patterson|date=August 4, 2013|accessdate=September 10, 2013}}</ref>
 
In October {{year|2014}}, [[Tanner Jacobi]] found a predecessor for this pattern based on a soup from [[Adam P. Goucher]]'s [[apgsearch]] script,<ref name="post13863" /> which was eventually optimized to a {{gliders|6|brief}}-glider synthesis<ref>{{cite web|url=http://www.conwaylife.com/forums/viewtopic.php?f=2&t=1452&start=50#p14192|title=Soup search results|author=Tanner Jacobi|date=November 8, 2014|accessdate=November 9, 2014}}</ref> in November.


==See also==
==See also==
*[[List of common oscillators]]
*[[Snake pit]]


==References==
==References==
<references />
<references>
<ref name="post78873">{{LinkForumThread
|format = ref
|title  = Re: Thread for basic questions
|p      = 78873
|author = Dave Greene
|date  = July 3, 2019
}}</ref>
<ref name="post13863">{{LinkForumThread
|format = ref
|title  = Re: Soup search results
|p      = 13863
|author = Tanner Jacobi
|date  = October 15, 2014
}}</ref>
</references>


==External links==
==External links==
*[http://www.argentum.freeserve.co.uk/lex_f.htm#foreandback Fore and back] at the Life Lexicon
{{LinkLexicon|lex_f.htm#foreandback}}
{{LinkCatagolue|xp2_ca1n0brz330321}}
{{LinkPentadecathlonObject|24P2.142}}
 
{{Symmetry|180degree|osc=flip}}
__NOTOC__

Revision as of 02:46, 18 March 2020

Fore and back
2ob2o2b$2obobob$6bo$3ob3o$o6b$bobob2o$2b2ob2o! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ AUTOSTART ]] #C [[ GPS 2 THUMBSIZE 2 ]]
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Pattern type Oscillator
Oscillator type Billiard table
Number of cells 24
Bounding box 7 × 7
Frequency class 30.6
Period 2
Mod 1
Heat 4
Volatility 0.15
Strict volatility 0.15
Rotor type Pole 2
Discovered by Achim Flammenkamp
Year of discovery 1994

Fore and back (or complementary blinker[1]) is a period-2 oscillator that was found by Achim Flammenkamp on July 12, 1994.[2] Its rotor is the same as the blinker.

Commonness

Fore and back is about the thirty-eighth most common naturally-occurring oscillator in Achim Flammenkamp's census, being less common than boat on spark coil and block on griddle, about as common as 21P2, and more common than trans-block on long hook eating tub and trans-beacon down on long hook.[3] It is the most common oscillator that is generally agreed to be a billiard table, though some instead give this title to the more common test tube baby, which counts under a looser definition.[4]

Synthesis

In August 2013, a 24-glider synthesis of this oscillator was found by Martin Grant, based on a soup provided by Lewis Patterson. Several days later Mark Niemiec improved this result, having found a 20-glider synthesis.[5]

In October 2014, Tanner Jacobi found a predecessor for this pattern based on a soup from Adam P. Goucher's apgsearch script,[6] which was eventually optimized to a 6-glider synthesis[7] in November.

See also

References

  1. ↑ "Complementary blinker". The Life Lexicon. Stephen Silver. Retrieved on December 3, 2018.
  2. ↑ Dean Hickerson's oscillator stamp collection. Retrieved on March 14, 2020.
  3. ↑ Achim Flammenkamp (September 7, 2004). "Most seen natural occurring ash objects in Game of Life". Retrieved on January 15, 2009.
  4. ↑ Dave Greene (July 3, 2019). Re: Thread for basic questions (discussion thread) at the ConwayLife.com forums
  5. ↑ Lewis Patterson (August 4, 2013). "Synthesising Oscillators". Retrieved on September 10, 2013.
  6. ↑ Tanner Jacobi (October 15, 2014). Re: Soup search results (discussion thread) at the ConwayLife.com forums
  7. ↑ Tanner Jacobi (November 8, 2014). "Soup search results". Retrieved on November 9, 2014.

External links


Retrieved from "https://conwaylife.com/w/index.php?title=Fore_and_back&oldid=70210"