Additional Examples of Turing Machines

The Excel file that you can download from the home page of this website already has some fine examples of Turing Machines that you can easily use. These are named UN+1, UNx2, XN+1, XNx2, EUC, and the Universal Turing Machine. Each of these six examples are exactly the ones that Sir Roger Penrose described in his book The Emperor's New Mind.

After I had constructed the Excel file to run these Turing Machines (i.e., the one that you can download from the Home page of this website), I decided to try to build and run some Turing Machines of my own. I saved these in a couple of Excel files that you can also download for yourself by clicking on either of the icons below.

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Clicking on the UN icon above will download for you an Excel file with examples of Turing Machines that work with data in Unary Notation. Similarly, the XN icon will give you an Excel file with examples of Turing Machines that work with data in Expanded Binary Notation.

The examples are of varying complexity. You may notice that the example UN+2 is fairly simple, but something like XN-XN (which computes the difference between two numbers in Expanded Binary Notation) is quite elaborate.

There are many ways in which a problem can be done. The examples I provided are not the most efficient, though I do believe that they always give the correct answer. You are certainly welcome to try to come up with better algorithms to accomplish the same effect. In fact, I encourage you to do so.