{"provider_name":"Hatena Blog","categories":["\u6570\u5b66","Python"],"author_url":"https://blog.hatena.ne.jp/inamori/","version":"1.0","url":"https://inamori.hateblo.jp/entry/20090805/p1","published":"2009-08-05 00:00:00","type":"rich","height":"190","author_name":"inamori","image_url":null,"description":"\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u30aa\u30a4\u30e9\u30fc http://projecteuler.net/ Q245. (n - \u03c6(n)) / (n - 1)\u3092\u7d04\u5206\u3057\u3066\u5206\u5b50\u304c1\u306b\u306a\u308b\u3001\u5408\u6210\u6570\u306e1 < n \u2264 2\u00d71011\u306e\u7dcf\u548c\u3092\u6c42\u3081\u3088\u3002 \u6700\u96e3\u554f\u984c\u3060\u305d\u3046\u3060\u304c\u3001\u3055\u307b\u3069\u3066\u3053\u305a\u3089\u306a\u304b\u3063\u305f\u3002 \u307e\u305a\u3001n\u3092\u7d20\u56e0\u6570\u5206\u89e3\u3057\u3066\u3079\u304d\u4e57\u306e\u9805\u304c\u3042\u308b\u3068\u30c0\u30e1\u306a\u306e\u306f\u3059\u3050\u306b\u308f\u304b\u308b\u3002\u307e\u305f\u3001\u5076\u6570\u3082\u30c0\u30e1\u3002n\u304c2\u3064\u306e\u7d20\u6570\u306e\u7a4d\u3067\u3042\u308b\u3068\u304d\u3001 n = p1p2 (p1 + p2 - 1) / (p1p2 - 1) = 1 / m (p1 - m)(p2 - m) = m2 - m + 1 m2 - m + 1\u306e\u7d20\u56e0\u6570\u5206\u89e3\u306f\u3001n2 + 1\u306e\u3068\u304d\u3068\u540c\u3058\u3075\u308b\u3044\u7684\u306a\u624b\u6cd5\u304c\u305d\u306e\u307e\u307e\u4f7f\u2026","provider_url":"https://hatena.blog","title":"Project Euler 245","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Finamori.hateblo.jp%2Fentry%2F20090805%2Fp1\" title=\"Project Euler 245 - inamori\u2019s diary\" 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://inamori.hateblo.jp/","blog_title":"inamori\u2019s diary","width":"100%"}