English

Computing $\sqrt{2}$ with FRACTRAN

Programming Languages 2024-12-24 v1

Abstract

The FRACTRAN programs 2\sqrt{2}GAME and NR2\sqrt{2}GAME are presented, both of which compute the decimal expansion of 2\sqrt{2}. Our 2\sqrt{2}GAME is analogous to Conway's PIGAME program. In fact, our proof carries over to PIGAME to produce a simpler proof of Conway's theorem as well as highlight how the efficiency of the program can be improved. NR2\sqrt{2}GAME encodes the canonical example of the Newton--Raphson method in FRACTRAN.

Cite

@article{arxiv.2412.16185,
  title  = {Computing $\sqrt{2}$ with FRACTRAN},
  author = {Khushi Kaushik and Tommy Murphy and David Weed},
  journal= {arXiv preprint arXiv:2412.16185},
  year   = {2024}
}
R2 v1 2026-06-28T20:44:15.499Z