{"html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fall-for-nothing.com%2Fentry%2F2020%2F10%2F30%2F171536\" title=\"\u6570\u5217\u306e\u548c\u304b\u3089\u4e00\u822c\u9805\u3092\u6c42\u3081\u308b\u3068\u304d\u306e\u5834\u5408\u5206\u3051 - \u7a7a\u8ad6\u4e0a\u306e\u7802\u3001\u697c\u95a3\u4e0a\u306e\u673a\u3002\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","blog_url":"https://all-for-nothing.com/","provider_url":"https://hatena.blog","categories":["\u6570\u5b66"],"provider_name":"Hatena Blog","description":"\u6570\u5217 ${a_n}$ \u306e\u521d\u9805\u304b\u3089\u7b2c $n$ \u9805\u307e\u3067\u306e\u548c\u3092 $S_n$ \u3068\u3059\u308b\u3068\u304d, \u6b21\u306e\u7b49\u5f0f\u304c\u6210\u308a\u7acb\u3064. $$a _ n=\\begin{cases} S _ n-S _ {n-1} & (n \\geq 2)\\\\ S _ 1 & (n=1) \\end{cases}$$ \u6570\u5217 $a_n$ \u306e\u521d\u9805\u304b\u3089\u7b2c $n$ \u9805\u307e\u3067\u306e\u548c $S _ n$ \u304c $S _ n=2 ^ n$ \u3067\u3042\u308b\u3068\u304d, \u3053\u306e\u6570\u5217\u306e\u4e00\u822c\u9805\u3092\u6c42\u3081\u3088. $n\\geq2$ \u306e\u3068\u304d $a _ n=S _ n-S _ {n-1}$ \u306a\u306e\u3067 $a _ n=2 ^ n-2 ^ {n-1}=2 ^ {n-1}(2-1)=2 ^ {n-1}$ \u3067\u3042\u308a, \u2026","width":"100%","version":"1.0","title":"\u6570\u5217\u306e\u548c\u304b\u3089\u4e00\u822c\u9805\u3092\u6c42\u3081\u308b\u3068\u304d\u306e\u5834\u5408\u5206\u3051","author_name":"all_for_nothing","height":"190","author_url":"https://blog.hatena.ne.jp/all_for_nothing/","image_url":null,"published":"2020-10-30 17:15:36","type":"rich","url":"https://all-for-nothing.com/entry/2020/10/30/171536","blog_title":"\u7a7a\u8ad6\u4e0a\u306e\u7802\u3001\u697c\u95a3\u4e0a\u306e\u673a\u3002"}