You can find the specifications of all 43 of Skelet's highly non-regular machines (HNRs) on his page here. They are the 42 machines denoted "----" and the one denoted "BL_2" under "type" which do not write a 0 at the first step.

Below is the .txt file that I have been using to keep a record of the growth rates of various machines, as well as which machines have been proved so far.
record.txt

Below is the zip file, containing the proofs, the record (in proofs), the xcode project, the Turing program (in build/Debug), its source code files (.h and .cpp files), and intermediate files created while compiling (in xcode). To run it, the files "HNRs.txt" and "instr.txt" must stay in its directory.
Turing7-20-10.zip

If you would rather just browse (does not contain intermediate files)
July 24, 2010: BL_2 machine added as machine #43. You can also run Marxen & Buntrock's champion (as "machine #127").
Turing/

Instructions: You will need xcode to run the program. There are a few simple errors incurred in gcc, which I will iron out soon (or you can iron out). The file "instr.txt" goes in the build/Debug directory. It consists of five lines:
1. The # of the current machine (in which place, 1-42, it comes in skelet.ludost.net/bb/nreg.html). I will soon include the BL_2 machine.
2. How many steps to run it for. This is currently set to 10; you will probably want to run them for thousands of steps at least.
3. How long to make the tape. I have been able to work fairly easily with tapes as long as 600 symbols on a single monitor.
4. What place on the tape the head should start at.
5. The modulus for skipping the display of the tape. This is currently set to 1 (no skipping); on the other hand, if you display the contents of the tape every million steps, you can run a machine for billions of steps in under an hour.

This is what you can do simply by compiling the program. If you need help editing it for further capability, do not hesitate to e-mail me at

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Daniel Briggs
7/22/10