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by shagie 763 days ago
My favorite turning complete language is Fractran - https://en.wikipedia.org/wiki/FRACTRAN

    17 78 19 23 29 77 95 77  1 11 13 15  1 55
    -- -- -- -- -- -- -- -- -- -- -- -- -- --
    91 85 51 38 33 29 23 19 17 13 11  2  7  1
That computes prime numbers.

Iterate through the list (start with n = 2) and iterate through until the fraction is an integer. Repeat with the new number.

For this, after 2, the next value is 15 (when it gets to 15/2). Then it will be 825 (15 * 55/1). Then it will be 725 (825 * 29 / 33) and so on. At some point, n will be 2^x where the sequence of when the number is just a power of 2 will be: 2^2, 2^3, 2^5, 2^7, 2^11 and so on... the exponents of 2 are the prime sequence.

2, 15, 825, 725, 1925, 2275, 425, 390, 330, 290, 770, 910, 170, 156, 132, 116, 308, 364, 68, 4, 30 ...

https://oeis.org/A007542

https://news.ycombinator.com/item?id=35966537

https://softwareengineering.stackexchange.com/questions/2201...

https://web.archive.org/web/20150923211455/http://www.cs.vu....