user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: what is the conference series that belongs to the same conference event as radisson muehlebach hotel? 
Knowledge Triplets: Radisson Muehlebach Hotel, conferences.conference_venue.conferences, 34th World Science Fiction Convention
34th World Science Fiction Convention, conferences.conference.series, Worldcon
Radisson Muehlebach Hotel, conferences.conference.venue, 34th World Science Fiction Convention
34th World Science Fiction Convention, conferences.conference.venue, Radisson Muehlebach Hotel
34th World Science Fiction Convention, time.event.locations, Kansas City
Worldcon, conferences.conference_series.conference, 34th World Science Fiction Convention
Kansas City, location.location.events, 34th World Science Fiction Convention

Answer: Worldcon