64313
In the AD year numbering system , whether applied to the Julian or Gregorian calendars , AD 1 is immediately preceded by 1 BC , with nothing in between them ( there was no year zero ) .
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Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
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