"recreational mathematics" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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        "Any use of mathematics or logic whose primary purpose is recreation, though often with more serious characteristics."
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        "(mathematics) Any use of mathematics or logic whose primary purpose is recreation, though often with more serious characteristics."
      ],
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        "recreational mathematics"
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  "word": "recreational mathematics"
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Any use of mathematics or logic whose primary purpose is recreation, though often with more serious characteristics."
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        "(mathematics) Any use of mathematics or logic whose primary purpose is recreation, though often with more serious characteristics."
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