{"height":"190","blog_title":"Holograph1c Attract0r","author_url":"https://blog.hatena.ne.jp/mikan_alpha/","blog_url":"https://mikan-alpha.hatenablog.com/","provider_name":"Hatena Blog","description":"\u4eca\u65e5\u306f\u3053\u308c\u3092\u8a08\u7b97\u3057\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002 \\begin{align}\\sum_{n=0}^{\\infty} \\frac{1}{(2n)!!}\\end{align} \u5206\u6bcd\u306e\u3084\u3064\u306f\u4e8c\u91cd\u968e\u4e57\u3068\u547c\u3070\u308c\u308b\u3084\u3064\u3067\u3059\u3002\u968e\u4e57\u3092\u4e8c\u56de\u7e70\u308a\u8fd4\u3057\u305f\u3084\u3064 \u3068\u306f\u9055\u3046\u306e\u3067\u6ce8\u610f\u3057\u307e\u3057\u3087\u3046\u3002 \u4e00\u5fdc\u521d\u3081\u3066\u898b\u305f\u65b9\u5411\u3051\u306b\u3056\u3063\u304f\u308a\u8aac\u660e\u3059\u308b\u3068\u3001\u4e8c\u91cd\u968e\u4e57 \u306f\u6b63\u306e\u6574\u6570\u306e\u3046\u3061 \u4ee5\u4e0b\u306e\u3082\u306e\u3067\u304b\u3064 \u3068\u5076\u5947\u306e\u4e00\u81f4\u3059\u308b\u3082\u306e\u3092\u5168\u3066\u304b\u3051\u305f\u3082\u306e\u3067\u3059\u3002\uff08\u305f\u3060\u3057 \uff09 \\begin{align}5!! &= 5 \\times 3 \\times 1 = 15 \\\\8!! &= 8 \\times 6 \\times 4 \\times 2 = 384 \\\\1728!! &= \u2026","image_url":"https://cdn.blog.st-hatena.com/images/theme/og-image-1500.png","provider_url":"https://hatena.blog","width":"100%","published":"2019-04-05 15:44:46","categories":["\u6570\u5b66","\u81ea\u7136\u5bfe\u6570\u306e\u5e95"],"url":"https://mikan-alpha.hatenablog.com/entry/2019/04/05/154446","type":"rich","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fmikan-alpha.hatenablog.com%2Fentry%2F2019%2F04%2F05%2F154446\" title=\"\u4e8c\u91cd\u968e\u4e57\u3068\u30cd\u30a4\u30d4\u30a2\u6570 - Holograph1c Attract0r\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","version":"1.0","title":"\u4e8c\u91cd\u968e\u4e57\u3068\u30cd\u30a4\u30d4\u30a2\u6570","author_name":"mikan_alpha"}