'''Primer''' is a [[pattern]] that was constructed by [[Dean Hickerson]] on November 1, [[:Category:Patterns found in 1991|1991]] that produces a stream of [[lightweight spaceship]]s representing prime numbers. N is prime if and only if a lightweight spaceship is above the [[honeycomb]] at the bottom-left corner of the pattern at [[generation]] 120N ticks.<ref>PRIMES.LIF from [[Alan Hensel]]'s [http://www.ibiblio.org/lifepatterns/ lifep.zip pattern collection]. Accessed on July 28, 2009.</ref><ref>four-primers.rle.gz from [[Golly]]'s built-in pattern catalogue. Accessed on July 28, 2009.</ref> It was the first pattern created that computes prime numbers, though others have since been constructed using the same ideas (see [[glider gunless primer]]).
|name = Primer
|pname = primer
|c = 2953
|bx = 440
|by = 294
|symmetry = C1
|discoverer = Dean Hickerson
|discoveryear = 1991
|rulemin = B3/S23
|rulemax = B3/S23
|rulespecial = [[Conway's Game of Life|Conway Life]]
|isorulemin = B3/S23
|isorulemax = B3/S23
|plaintext = true
|rle = true
|hideimg = true
}}
'''Primer''' is a [[pattern]] that was constructed by [[Dean Hickerson]] on November 1, {{year|1991}} that produces a stream of [[lightweight spaceship]]s representing [[Prime number|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]] {{nowrap|120 N + 100}}.<ref>{{filename|PRIMES.LIF}} from [[Alan Hensel]]'s [http://www.ibiblio.org/lifepatterns/ {{filename|lifep.zip}} pattern collection]. Accessed on July 28, 2009.</ref><ref>{{CiteGollyPatternCollection|four-primers.rle.gz|accessdate=July 28, 2009}}</ref> It was the first known pattern created that computes prime numbers, though others have since been constructed based on the same ideas.<ref name="post6330" />
It works by using [[glider]]s to emulate a [http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes 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.
It works by using [[glider]]s to emulate a prime number sieve<ref>{{LinkWikipedia|Sieve_of_Eratosthenes|name=Sieve of Eratosthenes|nobullet=nobullet}}</ref>. Lightweight spaceships that move westward are deleted by gliders that represent positive odd integers if the lightweight spaceship represents a multiple of that number.
Note that the numbers 2 and 3 are not outputted; the stream of prime numbers starts with 5.
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 generation120 N + 100.[1][2] It was the first known pattern created that computes prime numbers, though others have since been constructed based on the same ideas.[3]
It works by using gliders to emulate a prime number sieve[4]. Lightweight spaceships that move westward are deleted by gliders that represent positive odd integers if the lightweight spaceship represents a multiple of that number.
