Fore and back (or complementary blinker) is a period 2 oscillator that was found by Achim Flammenkamp in July 1994. Its rotor is the same as the blinker.
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 griddle and block, about as common as 21P2, and more common than trans-block and long hook eating tub and trans-beacon down and long hook.
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.
In October 2014, Tanner Jacobi found a predecessor for this pattern based on a soup from Adam P. Goucher's apgsearch script, which was eventually optimized to a 6-glider synthesis in November.
- ↑ Achim Flammenkamp (September 7, 2004). "Most seen natural occurring ash objects in Game of Life". Retrieved on January 15, 2009.
- ↑ "Synthesising Oscillators". Retrieved on September 10, 2013.
- ↑ "Soup search results". Retrieved on November 9, 2014.
- 24P2.142 at Heinrich Koenig's Game of Life Object Catalogs