Primer

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Primer
Primer image
Pattern type Miscellaneous
Number of cells 2953
Bounding box 440×294
Discovered by Dean Hickerson
Year of discovery 1991

Primer is a pattern that was constructed by Dean Hickerson on November 1, 1991 that produces a stream of lightweight spaceships representing prime numbers. N is prime if and only if a lightweight spaceship escapes to the left of the pentadecathlon at the bottom-left corner of the pattern at generation 120N+100.[1][2] It was the first pattern created that computes prime numbers, though others have since been constructed using the same ideas (see glider gunless primer).

It works by using gliders to emulate a prime number sieve. Lightweight spaceships that move westward are deleted by gliders that represent positive integers if the lightweight spaceship represents a multiple of that number.

Image gallery

The stream of spaceships representing prime numbers

Videos

Primer outputting the prime numbers from 2 through 37

See also

References

  1. PRIMES.LIF from Alan Hensel's lifep.zip pattern collection. Accessed on July 28, 2009.
  2. four-primers.rle.gz from Golly's built-in pattern catalogue. Accessed on July 28, 2009.