I wrote following program for finding out which ring of integers of cyclotomic fields are unique factorization domains:
max_limit=100
i=3
while i <= max_limit:
K=CyclotomicField(i)
O_K=K.ring_of_integers()
print(i , O_K in UniqueFactorizationDomains())
i=i+1
This gives me output as false for all numbers. But this wiki article https ://en.wikipedia.org/wiki/List_of_number_fields_with_class_number_one#Cyclotomic_fields suggests that there are bunch of them for which the class number is actually 1 i.e. the rings are unique factorization domains. I don't understand where I went wrong?