R-pentomino

From LifeWiki

R-pentomino
Manipulate via Java
Pattern type	Methuselah
Lifespan	1103 generations
Number of cells	5
Bounding box	3×3
Discovered by	John Conway
Year of discovery	1970
Glider synthesis Fewest gliders 3 Java link click here RLE rpentomino_synth.rle
Pattern files Life 1.05 rpentomino_105.lif Life 1.06 rpentomino_106.lif Plaintext rpentomino.cells RLE rpentomino.rle

The R-pentomino is a methuselah that was found by John Conway in 1970.^[1] It is by far the most active polyomino with less than six cells; all of the others stabilize in at most 10 generations, but the R-pentomino does not do so until generation 1103, by which time it has a population of 116. It releases a glider in generation 69, which was noticed by Richard K. Guy and was the first glider ever observed.

[edit] Predecessors

The R-pentomino has several different small predecessors which are of note because they naturally have a longer lifespan. There are three 5-cell grandparents of the R-pentomino (which each have a lifespan of 1105 generations) and three 6-cell predecessors that evolve into the R-pentomino after 5 generations (and thus have a total lifespan of 1108).

The three 5-cell grandparents of the R-pentomino.

Three 6-cell predecessors that each evolve into the R-pentomino at generation 5.

[edit] Stable pattern

The stable pattern that results from the R-pentomino has 116 cells and consists of eight blocks, six gliders, four beehives, four blinkers, one boat, one loaf, and one ship.

Generation 1103

[edit] See also

• 117P18
• B-52 bomber
• List of long-lived methuselahs

[edit] References

1. ↑ Gardner, M. (1983). "The Game of Life, Part III". Wheels, Life and Other Mathematical Amusements: 219, 223, W.H. Freeman. 

[edit] External links

• New Methuselah Records at Game of Life News
• R-pentomino at Eric Weisstein's Treasure Trove of Life
• R-pentomino at the Life Lexicon