User blog comment:KurohaKafka/Turing-incomplete/@comment-1605058-20171028202017/@comment-1605058-20171029101538

There was a minor mistake in my program which didn't make all the non-terminating trees print. There turn out to be 15 of them: [[], [[[], [, []]], []], [], [, []]] [[[], [, []], ], [[[], [, []]]], []] [[[], [[], [], []], [], [, []]], []] [[], [[], [[[], [, []]]], ], [], []] [[[[], [, []], ], [], ], [], []] [[[], [[[], [, []]], []], ], [], []] [[[[], [[], [], []], []], ], [], []] [[[[], [, []], ], ], [, []], []] [[[], [[], ], [, ], [], []], []] [[[[], [[], [], []], [[], []]], []], []] [[[], [[], [[[], [, []]]], []], []], []] [[[], [[[], [[], [], []]], []], []], []] [[[[[], [, []], [[], []]], []], []], []] [[[[], [[], [[], []], []], []], []], []] [[[[[], [[], [], []], []], []], []], []]

Here [] denotes a tree with one vertex (labelled S) and [A, B] a tree with left and right subtrees respectively A, B. I haven't checked that all of them don't terminate, but I would believe neither does (they all reach the size of 100000).