question: How many United States presidents did not have any biological children?
answerText: 5
questionEntity.name: Q30
questionEntity.entityType: entity
questionEntity.label: United States of America
questionEntity.mention: United States
answerEntity.name: Q23
answerEntity.label: George Washington
answerEntity.name: Q11813
answerEntity.label: James Madison
answerEntity.name: Q11817
answerEntity.label: Andrew Jackson
answerEntity.name: Q12325
answerEntity.label: James Buchanan
answerEntity.name: Q35286
answerEntity.label: Warren G. Harding