Rfractran (version 1.0.1)

Rfractran-package: tools:::Rd_package_title("Rfractran")

Description

tools:::Rd_package_description("Rfractran")

Author

tools:::Rd_package_author("Rfractran") Maintainer: tools:::Rd_package_maintainer("Rfractran")

Details

The DESCRIPTION file: tools:::Rd_package_DESCRIPTION("Rfractran") tools:::Rd_package_indices("Rfractran") FRACTRAN is an obscure yet tantalizing programming "language" invented by John Conway of "Game of Life" fame. The code consists of a sequence of fractions. The operation is simple. 1 - Initalize with an integer 2 - Multiply the integer by the first fraction. If an integer results, start again with the new integer. If not, try the next fraction. 3 - If no such multiplication yields an integer, terminate the program. One warning: there is a FRACTRAN program that can be found on the web which is supposed to generate the digits of pi. Unfortunately, it's known to have a bug which causes it not to work. So far nobody has found a correction for it.

References

https://esolangs.org/wiki/Fractran https://oeis.org/wiki/List_of_FRACTRAN_programs_to_compute_core_sequences

Examples

##Not Run
# addition:  { 3/2 } . Enter 2^a*3^b and get 3^(a+b) answer when terminated

# multiplication:  
# { 455/33, 11/13, 1/11,  3/7, 11/2, 1/3 } 
# then  enter 2^a*3^b  Terminates with  5^(a*b)

# prime generator (This function never terminates.)
#start with 10, feed to [7/3 99/98 13/49 39/35 36/91 10/143 49/13 7/11 1/2 91/1]
# and whenever the result of a run is of the form 10^p , p is prime