Yours is also right. A number sequence can have

来源: 于 2010-07-04 15:24:47 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

more than one possibility.

Now please focus on 130 because I am unable to answer it. I have tried many different possibilities and strategies, but none have worked. Thank you.

By the way, I know 180 now. ;) It is 20.

Happy Independence Day, everyone~~~