Thanks for your Q. I can do.

来源: 于 2011-01-26 08:40:22 [旧帖] [给我悄悄话] 本文已被阅读：次

1) 9781 is Prime number.

2)Y is not 0,let y=Pi1^a1*Pi2^a2*...Pim^am

3)We have (x+1)(x-1)=9781y^2=(9781Pi1^t1*...Pim^tm)(Pi1^s1*...Pim^sm),...

4)(x+1)-(x-1)=2=1*2=(9781Pi1^c1*...Pim^cm-Pi1^d1*...Pim^dm)*Pi1^e1*...Pim^em

  So,Pi1=2,The right >=4. Contradiction, no solution if y>0.