{"description":"\u30af\u30ea\u30b9\u30de\u30b9\u3067\u3059\u304b\u3002\u4f55\u5e74\u304b\u524d\u306b\u30c8\u30e0\u30fb\u30ec\u30f3\u30b9\u30bf\u30fc\uff08Tom Leinster\uff09\u304c\u300c\u30af\u30ea\u30b9\u30de\u30b9\u306b\u306f\u30c8\u30dd\u30b9\u3092\u52c9\u5f37\u3057\u3088\u3046\u300d\u3068\u304b\u66f8\u3044\u3066\u307e\u3057\u305f\u304c\u3001\u30c8\u30dd\u30b9\u3058\u3083\u306a\u304f\u3066\u30e2\u30ca\u30c9\u306e\u8a71\u3002Maybe\u30e2\u30ca\u30c9\uff08\u30aa\u30d7\u30b7\u30e7\u30f3\u30fb\u30e2\u30ca\u30c9\u3001\u4ed8\u70b9\u30e2\u30ca\u30c9\u306a\u3069\u3068\u3082\u547c\u3076\uff09\u306f\u30e2\u30ca\u30c9\u306e\u306a\u304b\u3067\u3082\u4e00\u756a\u7c21\u5358\u306a\u3082\u306e\u3067\u3057\u3087\u3046\u3002Maybe\u30e2\u30ca\u30c9\u3068\u6b63\u5b9f\u6570\u306e\u639b\u3051\u7b97\u3092\u7d44\u307f\u5408\u308f\u305b\u305f\u30e2\u30ca\u30c9\u3092\u5b9a\u7fa9\u3057\u3066\u307f\u307e\u3059\u3002\u6b63\u5b9f\u6570\u306e\u639b\u3051\u7b97\u3068\u4e00\u70b9\u8ffd\u52a0\u306b\u3088\u308b\u30e2\u30ca\u30c9R+ = {x\u2208R | x \uff1e 0} \u3068\u3057\u307e\u3059\u3002\u307e\u305f\u3001O = {0} \u3068\u3057\u307e\u3059\u3002\u96c6\u5408X\u306b\u5bfe\u3057\u3066\u3001X\u00d7R+ + O \u3068\u3044\u3046\u5bfe\u5fdc\u3092\u95a2\u624b\u306b\u62e1\u5f35\u3057\u305f\u3082\u306e\u3092F\u3068\u3057\u307e\u3059\u3002\u8a73\u3057\u304f\u66f8\u304f\u3068\uff1a F\u306fSet\u4e0a\u306e\u81ea\u5df1\u95a2\u624b\u3002 X\u2208|Set| \u306b\u5bfe\u3057\u3066\u3001F(X\u2026","blog_url":"https://m-hiyama.hatenablog.com/","type":"rich","author_name":"m-hiyama","image_url":null,"height":"190","url":"https://m-hiyama.hatenablog.com/entry/20151224/1450928418","published":"2015-12-24 12:40:18","provider_name":"Hatena Blog","version":"1.0","author_url":"https://blog.hatena.ne.jp/m-hiyama/","categories":["\u96d1\u8a18\uff0f\u5099\u5fd8"],"title":"\u8cea\u91cf\u30e2\u30ca\u30c9","blog_title":"\u6a9c\u5c71\u6b63\u5e78\u306e\u30ad\u30de\u30a4\u30e9\u98fc\u80b2\u8a18 (\u306f\u3066\u306aBlog)","provider_url":"https://hatena.blog","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fm-hiyama.hatenablog.com%2Fentry%2F20151224%2F1450928418\" title=\"\u8cea\u91cf\u30e2\u30ca\u30c9 - \u6a9c\u5c71\u6b63\u5e78\u306e\u30ad\u30de\u30a4\u30e9\u98fc\u80b2\u8a18 (\u306f\u3066\u306aBlog)\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","width":"100%"}