Python 3.6
def Collatzletter():
global tocollatz
operations=0
agustment=0
convert={'a':'bc','b':'a','c':'aaa'}
while len(tocollatz)>1:
tocollatz=tocollatz[2:]+convert[tocollatz[0]]
operations+=1
agustment+=2
print(tocollatz.rjust(len(tocollatz)+agustment,' '))
print ('Wow!, that took ' + str(operations)+" times to get to just 'a'")
The Collatz thing with a, b and c. Ialso added in a counter (named operations) where it counts how many times it has to happen to reach only 1 a and I added in a rjust which makes it look like how it does on the wikipedia site in the description.
My output for aaa:
aaa
abc
cbc
caaa
aaaaa
aaabc
abcbc
cbcbc
cbcaaa
caaaaaa
aaaaaaaa
aaaaaabc
aaaabcbc
aabcbcbc
bcbcbcbc
bcbcbca
bcbcaa
bcaaa
aaaa
aabc
bcbc
bca
aa
bc
a
Wow!, that took 24 times to get to just 'a'