FRACTRAN is an esoteric programming language created in 1996 by John Conway.

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FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Conway. A FRACTRAN program is an ordered list of positive fractions together with an initial positive integer input n. The program is run by updating the integer n as follows: for the first fraction f in the list for which nf is an integer, replace n by nf repeat this rule until no fraction in the list produces an integer when multiplied by n, then halt. Read more on Wikipedia...

• FRACTRAN Wikipedia page
• FRACTRAN first developed in University of Cambridge, Sidney Sussex College
• FRACTRAN on Esolang
• Read more about FRACTRAN on the web: 1.