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Summary
DescriptionRecursive enumeration of all halting Turing machines.gif
English: Shows an algorithm to enumerate the set of all Turing machines halting on a fixed input x: Simulate all Turing machines (enumerated in green on vertical axis) step by step (horizontal axis), using the shown diagonalization scheduling (red line). If a machine terminates, print its number. This way, the number of each terminating machine is eventually printed. In the example, the algorithm prints 9, 13, 4, 15, 12, 18, 6, 2, 8, 0, ...
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