Editing Esoteric programming language (section)

=== FRACTRAN ===
A [[FRACTRAN]] program is an ordered list of positive fractions together with an initial positive integer input <math>n</math>. The program is run by multiplying the integer <math>n</math> by the first fraction <math>f</math> in the list for which <math>nf</math> is an integer. The integer <math>n</math> is then replaced by <math>nf</math> and the rule is repeated. If no fraction in the list produces an integer when multiplied by <math>n</math>, the program halts. FRACTRAN was invented by mathematician [[John Horton Conway|John Conway]].<ref>{{cite book |last1=Kneusel |first1=Ronald |title=Strange Code: Esoteric Languages That Make Programming Fun Again |date=2022 |publisher=No Starch Press |isbn=978-1718502406 |page=217 |ref=kneusel-strange-code-fractran}}</ref>