"lacunary function" meaning in English

{
  "forms": [
    {
      "form": "lacunary functions",
      "tags": [
        "plural"
      ]
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  ],
  "head_templates": [
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      "args": {},
      "expansion": "lacunary function (plural lacunary functions)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "kind": "other",
          "name": "English entries with incorrect language header",
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          "langcode": "en",
          "name": "Mathematics",
          "orig": "en:Mathematics",
          "parents": [
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            "Sciences",
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          "source": "w"
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      ],
      "glosses": [
        "A function defined by a lacunary series, especially one which cannot be analytically continued outside its domain of convergence."
      ],
      "id": "en-lacunary_function-en-noun-fOX9fXe-",
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "lacunary series",
          "lacunary series"
        ],
        [
          "domain",
          "domain"
        ],
        [
          "convergence",
          "convergence"
        ]
      ],
      "raw_glosses": [
        "(mathematics) A function defined by a lacunary series, especially one which cannot be analytically continued outside its domain of convergence."
      ],
      "topics": [
        "mathematics",
        "sciences"
      ],
      "wikipedia": [
        "lacunary function"
      ]
    }
  ],
  "word": "lacunary function"
}

{
  "forms": [
    {
      "form": "lacunary functions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "lacunary function (plural lacunary functions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
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      ],
      "glosses": [
        "A function defined by a lacunary series, especially one which cannot be analytically continued outside its domain of convergence."
      ],
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "lacunary series",
          "lacunary series"
        ],
        [
          "domain",
          "domain"
        ],
        [
          "convergence",
          "convergence"
        ]
      ],
      "raw_glosses": [
        "(mathematics) A function defined by a lacunary series, especially one which cannot be analytically continued outside its domain of convergence."
      ],
      "topics": [
        "mathematics",
        "sciences"
      ],
      "wikipedia": [
        "lacunary function"
      ]
    }
  ],
  "word": "lacunary function"
}