0088名無しさん@お腹いっぱい。(神奈川県)垢版 | 大砲2018/11/22(木) 18:03:26.71ID:2/GtgQ8D (17!/(18-k)!)/(k-1)!+(15!/(16-k)!)/(k-1)!+(13!/(14-k)!)/(k-1)!+(11!/(12-k)!)/(k-1)!+(9!/(10-k)!)/(k-1)!+(7!/(8-k)!)/(k-1)!+(6!/(7-k)!)/(k-1)!+(5!/(6-k)!)/(k-1)!+(4!/(5-k)!)/(k-1)!,k=15