# De Mol's Collatz 2-tag system (a -> bc, b -> a, c -> aaa) as UTS #35
# transform rules. From aaa, the run replicates
# https://en.wikipedia.org/wiki/Tag_system and halts at Ma (value 1).
# Run:  python3 uts35.py collatz.txt aaa
M a [abc] ([abc]*) > M $1 b c ;
M b [abc] ([abc]*) > M $1 a ;
M c [abc] ([abc]*) > M $1 a a a ;