→ a88241050 :n=2001為一解 04/29 23:12
→ doom8199 :S(n) + 2S(s(n)) = S(2007) = 9 → S(n)=3 04/29 23:18
→ doom8199 :好像還要考慮進位問題 OTZ 04/29 23:21
→ liengpi :出自2007 AMC12 04/29 23:31
→ oneway01 :n=1977, 1980, 1983, 2001 04/29 23:57
推 TOOYA :這臉打得好響啊 04/30 01:16