From LifeWiki
Jump to navigation Jump to search
x = 3, y = 3, rule = B3/S23 3o$obo$obo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]]
Pattern type Methuselah
Number of cells 7
Bounding box 3×3
Lifespan 173 generations
Final population 55
L/I 24.7
F/I 7.9
F/L 0.318
L/MCPS 24.7
Discovered by John Conway
Year of discovery 1970

Pi-heptomino (or pi; sometimes called blasting cap at MIT after its shape at generation 1[1]) is a common heptomino that stabilizes at generation 173, leaving behind six blocks, five blinkers and two ponds. The name "pi" is also applied to some slight variations of this object that follow that same evolutionary sequence – in a pi ship, for example, the pi-heptomino itself never actually arises. Forms that are synonymous with the pi-heptomino are displayed below.

In April 1992, Bill Gosper discovered that two blocks can be used to eat a pi, as shown below. The eating reaction takes 65 generations to complete. Gosper also discovered in the same month that a pi, along with two blocks and two blinkers, can be used to create a queen bee shuttle.

Image gallery

Generation 1 of pi-heptomino
A grandparent (a pentaplet) and parent (a hexomino) of pi
An alternative parent of generation 1
A pi eater
RLE: here
Another pi eater
RLE: here
This pattern, which resembles the word "Pi", evolves exactly like the Pi-heptomino after two generations, stabilizing at generation 174.

See also


  1. "Blasting cap". The Life Lexicon. Stephen Silver. Retrieved on May 14, 2016.

External links