有沒有好辦法?

來源: 2011-12-31 17:20:15 [舊帖] [給我悄悄話] 本文已被閱讀:

 

Let N denote the number of 8-tuples (a_1, a_2, \dots, a_8) of real numbers such that a_1 = 10 and

\left|a_1^{2} - a_2^{2}\right| = 10

\left|a_2^{2} - a_3^{2}\right| = 20

\cdots

\left|a_7^{2} - a_8^{2}\right| = 70

\left|a_8^{2} - a_1^{2}\right| = 80

Determine the remainder obtained when N is divided by 1000.

 

先在此謝過。